Are either of you exporting long videos? Around an hour or so? Understand that encoding is not a linear process, so the bar could go up to any percentage in a short amount of time and take longer at others. If it stays for longer than several hours then it probably really is stuck. I would try reinstalling Shotcut and exporting your videos to a different directory…
Another issue might be that there is little free space on your C: or whatever drive. Remember that ~1 hour of video is ~13 gb of data, and things start to get wonky if your hard drive is more than ~80% full. So if the results of your video may go over the limit of your drive, then most likely it would be causing this problem. Try clearing up enough space so that your video has enough room to stay under ~80% on your drive.
I hope this helps or that it’s enough. If problems still persist then it is most likely an issue with Shotcut itself and we’ll continue from there.