That was at the start, we were grinding and we go to the point where we all suppose to split up, but instead all I saw is people going straight to the certain point and repeat the same part about 3 times and most of the people died afterwards. The weird there's also an error pop and I don't think it was for me alone, since others saw it also.

I saw this a long time ago. I think it is a client problem.
what i did to get rid of it was just restart the client