Can't upload videos

I've tried restarting the app, turning wifi off and on, deleting my cache, deleting my history, deleting and reinstalling the app, nothing has worked. The videos just keep getting stuck during the upload at 70%, 96%, or whatever percentage. I've tried opening a support chat, but now when I try to reply to it, it never sends! I'm just so frustrated and I have no idea what I'm doing wrong. I've done an account check too and everything was fine.