Thanks for the comment!
I don't know how long you've been uploading, but things were even more shaky when I started in December. I sometimes had to keep trying for multiple hours on 4 seperate browsers.

The only advice I can give you is try using "handbrake" to compress your videos and try uploading vids less than 10 minutes for now.

I dunno how powerful a tablet/laptop is but a dedicated laptop is definitely better for editing