Unable to submit the form: stuck at "please wait" message

Also, please check the website on desktop, tablet and smartphone if you can. I upsized manually on desktop.

http://medexplans.com/get-a-quote.html

 When I filled in the form and clicked Submit button it shows wait moment, but then nothing happens even after 10min waiting.

I checked your form and I was able to do a test submission from the direct form URL. But when I tried it on your webpage, I was able to replicate the issue. 

Please try to re-embed the form using the iFrame method. It is possible that the scripts on your web page are having conflicts with the scripts on the form.