I'm new to this forum and also to OTRS. I'll be thankful if you can help me trying to solve my problem

I tried to solve it alone, but after a few hours on forums, I ask it to you.
The LDAP account I use is correctly configured in the AD (we have another system running in the company, and this one is working as I want (It's our prod system). I even tested to take out the config.pm from the one that was working, to put it on the other one, but without any success.
Maybe there is something that i'm missing ...
Thanks in advance for your help.