Problem with a form

Do you have a screen shot of what's happening? In the form settings, you can choose what happens after you click the "Submit" button, try playing around with these settings and see if it starts interacting like you want it to.

That's definitely something buggy on the Smartsheet side, the form submission should be quick and easy. If you've already tried recreating the form without solving the problem, I might suggest making a new sheet. I've found sometimes that the sheets themselves just get buggy, and starting from scratch can fix it. If that's not a reasonable solution, like if you have lots of connections across other dashboards/reports with that specific sheet, try submitting a help request.