Cant connect to friend it says it is "using different class servers" need help

[Rextimina]

For awhile now my gmod has been saying that different class server thing every time i try to connect to my friend.
I have gotten rid of a bunch of mods, restarted steam, reinstalled gmod.
Nothing has worked so far and i have no clue what the problem is.

[Bo98]

Opt-out of the dev branch.