diff --git a/redbot/core/bot.py b/redbot/core/bot.py
index 574c7cafcd9..c6e410c55b8 100644
--- a/redbot/core/bot.py
+++ b/redbot/core/bot.py
@@ -199,7 +199,6 @@ async def prefix_manager(bot, message) -> List[str]:
             if cli_flags.mentionable:
                 return when_mentioned_or(*prefixes)(bot, message)
             return prefixes
-        kwargs["case_insensitive"] = True
         if "command_prefix" not in kwargs:
             kwargs["command_prefix"] = prefix_manager