This Error 
duplicate key value violates unique constraint "mail_channel_partner_partner_unique" DETAIL: Key (channel_id, partner_id)=(1, 4192) already exists. 

I can't create a user or log in at all.

I tried to check the issue in the database by looking at the mail_channel_partner table, but I couldn't find the cause of the error and I also searched in the mail_channel_partner table and checked the partner_id , but there was no data being created as mentioned in the error.

This error occurred after I deleted all data in res_groups and restored res_groups from my latest backup into the main database.

I'm not sure what caused this issue or how to fix it.