Usergroups Edit creates another custom usergroup

[KeyHunterz]

Hello everyone, I'm running Vbulletin version 3.7.3 and i have a little issue which i don't know how to solve. Everytime I edit an existing User group such as Administrator, the moment i click on Update, A new usergroup is created which is the exact copy of the edited one. I tried to update the skin, rebuilt the cache and all that..... none of it worked.

Step one, I click on edit and than i click on Update :



Next thing i know a copy is created, and the original is unedited.



Please help?

Thank you