That’s odd. I upload videos taken on iPhone now and again and have never had issues. weird!!!!

Yeah, I had issues with video that was shot using iphone and had to export it with Media Encoder, but that was it. Right now, the video is uploading but soooo incredibly slow. No idea why, everything else is working fine. Thanks for your comment. 

It’s only happened to me once when the file type wasn’t compatible 

Hi, just wanted to ask if anybody else has the same issue since I couldn't find any solutions. 
I can't upload videos to Twitter for a couple of days now. I've checked the upload requirements, how long it is and all that, plus I did upload other videos in the past few months without any problems. I've used the same video on FB and IG, but no luck on Twitter. Any advice is welcome. Thanks!

Twitter can't upload video