diff --git a/src/Public/Add-CCMGroup.ps1 b/src/Public/Add-CCMGroup.ps1
index b81ff9e..93f1f5c 100644
--- a/src/Public/Add-CCMGroup.ps1
+++ b/src/Public/Add-CCMGroup.ps1
@@ -82,18 +82,8 @@ function Add-CCMGroup {
         $body = @{
             Name        = $Name
             Description = $Description
-            Groups      = if (-not $processedGroups) {
-                @()
-            }
-            else {
-                @(, $processedGroups)
-            }
-            Computers   = if (-not $processedComputers) {
-                @()
-            }
-            else {
-                @(, $processedComputers)
-            }
+            Groups      = @($processedGroups)
+            Computers   = @($processedComputers)
         } | ConvertTo-Json
 
         $irmParams = @{
diff --git a/src/Public/Add-CCMGroupMember.ps1 b/src/Public/Add-CCMGroupMember.ps1
index 24bfdff..ee8a1e5 100644
--- a/src/Public/Add-CCMGroupMember.ps1
+++ b/src/Public/Add-CCMGroupMember.ps1
@@ -62,8 +62,7 @@ function Add-CCMGroupMember {
         $ComputerCollection = [System.Collections.Generic.List[psobject]]::new()
         $GroupCollection = [System.Collections.Generic.List[psobject]]::new()
 
-        $id = Get-CCMGroup -Group $name | Select-Object -ExpandProperty Id
-        $current = Get-CCMGroup -Id $id | Select-Object *
+        $current = Get-CCMGroupMember -Group $name | Select-Object *
         $current.computers | ForEach-Object { $ComputerCollection.Add([pscustomobject]@{computerId = "$($_.computerId)" }) }
     }
 
@@ -71,47 +70,44 @@ function Add-CCMGroupMember {
         switch ($PSCmdlet.ParameterSetName) {
             { $Computer } {
                 foreach ($c in $Computer) {
-                    if ($c -in $current.computers.computerName) {
-                        Write-Warning "Skipping $c, already exists"
+                    $computerId = $computers | Where-Object { $_.Name -eq $c } | Select-Object -ExpandProperty Id
+                    if (-not $computerId) {
+                        Write-Warning "A computer with the name $c could not be found, skipping adding it to the group"
+                        continue
+                    }
+
+                    if ($computerId -in $current.computers.computerId) {
+                        Write-Warning "Skipping $c, already exists in this group"
                     }
                     else {
-                        $Cresult = $computers | Where-Object { $_.Name -eq "$c" } | Select-Object  Id
-                        $ComputerCollection.Add([pscustomobject]@{ computerId = "$($Cresult.Id)" })
+                        $ComputerCollection.Add([pscustomobject]@{ computerId = $computerId })
                     }
                 }
-
-                $processedComputers = $ComputerCollection
             }
             'Group' {
                 foreach ($g in $Group) {
-                    if ($g -in $current.groups.subGroupName) {
-                        Write-Warning "Skipping $g, already exists"
+                    $gId = $groups | Where-Object { $_.Name -eq $g } | Select-Object -ExpandProperty Id
+                    if (-not $gId) {
+                        Write-Warning "A group with the name $g could not be found, skipping adding it to the group"
+                        continue
+                    }
+
+                    if ($gId -in $current.groups.subGroupId) {
+                        Write-Warning "Skipping $g, already exists in this group"
                     }
                     else {
-                        $Gresult = $groups | Where-Object { $_.Name -eq $g } | Select-Object Id
-                        $GroupCollection.Add([pscustomobject]@{ subGroupId = "$($Gresult.Id)" })
+                        $GroupCollection.Add([pscustomobject]@{ subGroupId = $gId })
                     }
                 }
-                $processedGroups = $GroupCollection
             }
         }
 
         $body = @{
-            Name        = $Name
-            Id          = ($groups | Where-Object { $_.name -eq "$Name" } | Select-Object  -ExpandProperty Id)
-            Description = ($groups | Where-Object { $_.name -eq "$Name" } | Select-Object  -ExpandProperty Description)
-            Groups      = if (-not $processedGroups) {
-                @()
-            }
-            else {
-                @(, $processedGroups)
-            }
-            Computers   = if (-not $processedComputers) {
-                @()
-            }
-            else {
-                @(, $processedComputers)
-            }
+            Name        = $current.Name
+            Id          = $current.Id
+            Description = $current.Description
+            Groups      = @($GroupCollection)
+            Computers   = @($ComputerCollection)
         } | ConvertTo-Json -Depth 3
 
         Write-Verbose $body
diff --git a/src/Public/Get-CCMGroupMember.ps1 b/src/Public/Get-CCMGroupMember.ps1
index e15c521..481314d 100644
--- a/src/Public/Get-CCMGroupMember.ps1
+++ b/src/Public/Get-CCMGroupMember.ps1
@@ -41,37 +41,15 @@ function Get-CCMGroupMember {
 
     process {
         $Id = (Get-CCMGroup -Group $Group).Id
-        $irmParams = @{
-            Uri         = "$($protocol)://$hostname/api/services/app/Groups/GetGroupForEdit?id=$Id"
-            Method      = "GET"
-            ContentType = "application/json"
-            WebSession  = $Session
-        }
-
-        try {
-            $record = Invoke-RestMethod @irmParams -ErrorAction Stop
-        }
-        catch {
-            throw $_.Exception.Message
-        }
-
-        $cCollection = [System.Collections.Generic.List[psobject]]::new()
-        $gCollection = [System.Collections.Generic.List[psobject]]::new()
-
-        $record.result.computers | ForEach-Object {
-            $cCollection.Add($_)
-        }
-
-        $record.result.groups | ForEach-Object {
-            $gCollection.Add($_)
-        }
+        $result = Get-CCMGroup -Id $Id
 
         [pscustomobject]@{
-            Name        = $record.result.Name
-            Description = $record.result.Description
-            Groups      = @($gCollection)
-            Computers   = @($cCollection)
-            CanDeploy   = $record.result.isEligibleForDeployments
+            Id          = $result.Id
+            Name        = $result.Name
+            Description = $result.Description
+            Groups      = @($result.Groups | Where-Object { $_ })
+            Computers   = @($result.Computers | Where-Object { $_ })
+            CanDeploy   = $result.isEligibleForDeployments
         }
     }
 }
diff --git a/src/Public/Remove-CCMGroupMember.ps1 b/src/Public/Remove-CCMGroupMember.ps1
index 304befa..750b540 100644
--- a/src/Public/Remove-CCMGroupMember.ps1
+++ b/src/Public/Remove-CCMGroupMember.ps1
@@ -57,15 +57,27 @@ function Remove-CCMGroupMember {
 
     process {
         $currentMembers = Get-CCMGroupMember -Group $Group
-        $G = Get-CCMGroup -Group $Group
-        $currentMembers | Add-Member -MemberType NoteProperty -Name Id -Value $G.Id
+        $computers = Get-CCMComputer
+        $groups = Get-CCMGroup
 
         foreach ($c in $ComputerMember) {
-            $currentMembers.Computers = @($($currentMembers.Computers | Where-Object { $_.ComputerName -ne $c }))
+            $cId = $computers | Where-Object { $_.Name -eq $c } | Select-Object -ExpandProperty Id
+            if (-not $cId) {
+                Write-Warning "No computer with the name $c was found, cannot remove it from the group"
+                continue
+            }
+
+            $currentMembers.Computers = @($currentMembers.Computers | Where-Object { $_.computerId -ne $cId })
         }
 
         foreach ($g in $GroupMember) {
-            $currentMembers.Groups = @($($currentMembers.Groups | Where-Object { $_.subGroupName -ne $g }))
+            $gId = $groups | Where-Object { $_.Name -eq $g } | Select-Object -ExpandProperty Id
+            if (-not $gId) {
+                Write-Warning "No group with the name $g was found, cannot remove it from the group"
+                continue
+            }
+
+            $currentMembers.Groups = @($currentMembers.Groups | Where-Object { $_.subGroupId -ne $g })
         }
 
         if (-not $currentMembers.Groups) {
diff --git a/src/Public/Set-CCMGroup.ps1 b/src/Public/Set-CCMGroup.ps1
index aa1f256..077a580 100644
--- a/src/Public/Set-CCMGroup.ps1
+++ b/src/Public/Set-CCMGroup.ps1
@@ -57,7 +57,7 @@ function Set-CCMGroup {
             throw "Not authenticated! Please run Connect-CCMServer first!"
         }
 
-        $existing = Get-CCMGroup -Group $Group
+        $existing = Get-CCMGroupMember -Group $Group
     }
 
     process {
@@ -80,11 +80,11 @@ function Set-CCMGroup {
             Method      = "POST"
             ContentType = "application/json"
             Body        = @{
-                Id          = $($existing.id)
+                Id          = $existing.id
                 Name        = $Name
                 Description = $Description
-                Groups      = @()
-                Computers   = @()
+                Groups      = $existing.Groups
+                Computers   = $existing.Computers
             } | ConvertTo-Json
             WebSession  = $Session
         }