What should I do when I can't contact ATC?

I’m not sure if this belong in support or in general, so let me know if its not supposed to be in general.

Just as a lot of others I have had issues with the ATC (specifically the approach ATC). It doesn’t show up in the list of frequencies.
Ive looked around a bit and I am not totally sure what I should do when that happens.
I know can (should) change my username but to what? Should it be ATCISSUE or should I do like they do IRL when the communication with ATC fails and use the name SQUWK 7600? Or is there another one? I’m a bit lost atm and I have used ATCISSUE once but I feel like it would be better to use the SQUWK one (as I almost exclusively fly on the Expert server and have 0 violations in total I feel I should at least try to be as professional as possible and use the real life code).
I would be very grateful if I could get some help as to what to do.


Check this out!

Thanks a lot for the really fast help.