I'm also having trouble with Tapatalk. I can read but not send and it's been that way for days now. I got the app to simplify my forum reading into one app but it hasn't been very helpful since some other forums also have issues.
I hate having to use separate apps for each site. It's a waste of space! At least now I know that it's a known issue, I can remind myself to go the AVS app if I need to post something.