Hey, I tried to do some searching about this, but most of the discussion was around blocked IPs in Russia. We've had a few players from Turkey with ISP "Superonline" that are unable to login to Playfab... the error being "Unable to complete SSL connection". I got them to check the Playfab API link and Amazon's reachability page, which all work fine. I'm not sure if there's any other good procedures I can offer them or ways to debug, since the error is so vague.
I did have them test using their phones as hotspots though, which worked and implies that the problem is at the network level and not the PC itself.
Thanks.