Video playback problem

hello, the problem is that my friends via direct link do not have a video, which in turn is played by me, but I use a computer, and they have a phone

What kind of phone is that and what is the video format of the file you would like to play?

iphone xr and xiaomi, and the video format is mp4

Does the video play for them when you send them the link directly and not through Watch2Gether? You can also send me the link by email to and i have a look.