diff --git a/PluralKit.Bot/CommandMeta/CommandTree.cs b/PluralKit.Bot/CommandMeta/CommandTree.cs
index 02bcd374..34df66a1 100644
--- a/PluralKit.Bot/CommandMeta/CommandTree.cs
+++ b/PluralKit.Bot/CommandMeta/CommandTree.cs
@@ -190,7 +190,7 @@ public partial class CommandTree
             // if we *still* haven't matched anything, the user entered an invalid command name or system reference
             if (ctx.Parameters._ptr == previousPtr)
             {
-                if (ctx.Parameters.Peek().Length != 5 && !ulong.TryParse(ctx.Parameters.Peek(), out _))
+                if (ctx.Parameters.Peek().Length != 5 && !ctx.Parameters.Peek().TryParseMention(out _))
                 {
                     await PrintCommandNotFoundError(ctx, SystemCommands);
                     return;