diff --git a/changelog/unreleased/issue-21398.toml b/changelog/unreleased/issue-21398.toml
new file mode 100644
index 000000000000..6835d1a97e60
--- /dev/null
+++ b/changelog/unreleased/issue-21398.toml
@@ -0,0 +1,5 @@
+type = "f"
+message = "Fix an issue causing saving searches/dashboards after clearing the unit type to fail with error."
+
+pulls = ["21399"]
+issues = ["21398"]
diff --git a/graylog2-web-interface/src/views/components/aggregationwizard/units/FieldUnitPopover.tsx b/graylog2-web-interface/src/views/components/aggregationwizard/units/FieldUnitPopover.tsx
index ae0f5c9921c5..0ab96757aba0 100644
--- a/graylog2-web-interface/src/views/components/aggregationwizard/units/FieldUnitPopover.tsx
+++ b/graylog2-web-interface/src/views/components/aggregationwizard/units/FieldUnitPopover.tsx
@@ -71,7 +71,10 @@ const FieldUnitPopover = ({ field, predefinedUnit }: { field: string, predefined
     .map(({ abbrev, name }: Unit) => ({ value: abbrev, label: capitalize(name) })), [currentUnitType]);
   const toggleShow = () => setShow((cur) => !cur);
   const onUnitTypeChange = useCallback((val: string) => {
-    setFieldValue(`units.${field}`, { unitType: val || undefined, abbrev: undefined });
+    const fieldUnitSettings = val
+      ? { unitType: val, abbrev: undefined }
+      : undefined;
+    setFieldValue(`units.${field}`, fieldUnitSettings);
   }, [field, setFieldValue]);
 
   const badgeLabel = useMemo(() => {