Form staying open even after restarting Teams

Hi everyone. I am having an issue with some Forms linked to Teams staying open for very long times, even after the app has been restarted. This happens when the Form is added to a Team as a tab in one of the channels, not when people access it from a link. 

I need to use the usage stats from the form and the results are being skewed by the several-day-long submissions. 

I am sorry if this question is a known issue, I couldn't find anything online about it.

Thank you in advance for any help.