HELP! Subtitles dissapear in exported video

Hi, I’ve used shotcut for subtitling once before, but this time the outputted files only shows the correct subtitles for about 15-20 seconds before there are no more subtitles in the video. It looks perfectly fine on playback within the program.
I saw other people say you have to update shotcut, but that didn’t work either.

Please please help. I need to do this for a friend before he leaves my job at the end of the month. Thanks

Are you talking about embedded subtitles or converting them to text atop video using a filter. If text, how? There are different approaches. What is the frame rate of your project’s Video Mode?