Our form does not send when people click the submit button

When folks fill out my business app on their phone it doesn't send when they click the final submit button. How do I fix this?

Do you have a link with Jotform form in it for us to check? We're fine if it's an installable app, we only need access to test/try to submit the form. 

If it's a web app, we need to know how did you place the form there, like if it's by using one of our embed methods or an iframe by the form URL.