What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
If I understood you correctly, you want that Phone Number field only has one input field.
To achieve that all you need to do is to turn ON Input Mask option inside of your Form Builder. You can also remove Mask Value.
Hope this will help. Let us know if you need further assistance.