, 90 reporting, for Bangkok, is at Muang Thong, not CW. My 90 day online efforts also failed recently, although usually ok, and I had to go to Muang Thong. You can book an appointment to do it which avoids a queue, if there is one.
I thought that you had to do 90 day reporting at the relevant province office, ie where your tm30 says that you currently live, not at any immigration office '.