Apple Watch Series 4 and 5 keep pausing while exercising

I have an apple watch Series 5 and my teenage daughter has a series 4 when we are exercising they keep pausing. I would have thought it was my tattoo but since my daughter doesn't have one and it just started within the last month or two I don't know what the problem is. Has anyone else had this happen or know how to fix it even with auto-detection I still don't get the correct time and would basically have to work out longer to meet our goals. Not that that is completely horrible but if we are already doing 90 minutes a day I don't want to work out for an extra 15-30 minutes. As well has the tracking would still be inaccurate. I've tried all the tips online with no result. We have the latest updates and our devices have their own individual cellular plans if that makes a difference.