I was playing with my guild in Cyrodiil last night, everything went fine, it wasn't even lagging that bad. Then something weird happened. Our group wiped in a keep fight, we revived in another keep close by but about 7 or 8 group members were suddenly invisible. The other group members could still see us, we could see each other, we just couldn't see ourselves anymore. We all tried relogging, reloading UI, restarting the game (including the launcher), logging to other characters(which are all fine and nicely visible), then back to the invisible ones... nothing helped, we were still invisible.
We kept playing, it was kind of an extra challenge

(imagine playing in a zoomed out first person mode, not actually seeing what you're doing, or your horse or anything), some also logged off, bug reports were written. In one fight in Cyrodiil we realized that our own alliance members could see us but members from other alliances apparently couldn't. We still took aoe damage, but nobody attacked us when there were only enemy players around. NPCs however can still see us, and attack just as usual.
Somehow I hoped the problem would be gone today, but my character is still invisible. I spend most of my playtime in Cyrodiil but I don't want to play with a character that is invisible to enemy players. It's boring and feels like cheating.
When I tried to contact customer support today ingame I got this:

At first I didn't even see the error message, but something caught my eye and I highlighted things and well, that really is a problem, since I can't even send a bug report.
Please help and make me visible again