Note that you have nothing in conflict with any mod on the admin system or any mod that contains vscripts.

And check that you have access to the commands with the file "admins.txt" with your steam ID.

"C:\Program Files (x86)\Steam\steamapps\common\Left 4 Dead 2\left4dead2\ems\admin system"

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Note that you have nothing in conflict with any mod on the admin system or any mod that contains vscripts.

And check that you have access to the commands with the file "admins.txt" with your steam ID.

"C:\Program Files (x86)\Steam\steamapps\common\Left 4 Dead 2\left4dead2\ems\admin system"

I didn't download any new mods recently and the Admin ID is still there, i just stopped playing L4D2 for a few days and suddenly its not working anymore.

Very rare. I always use it on a local server of mine and it suits me perfectly. Even having several mods and none in conflict.

I don't know what it will be causing. Maybe a vscripts or mod file that prevents the use.

Have you tried the versus mode?