This is because you upgraded the version of Tik Tok, so the copy of Tik Tok, which is now the new version, will move up and down.

To create the effect of Tik Tok rolling subtitles, in fact, as long as you enter the desired text in the message bar at the top of the software, rolling subtitles will be automatically generated, and users can also set the background color, font size, color and style from it!