Sure you can. Limiting the form to only 1 submission per user is called "Unique submission" and it is really easy to configure.
This feature is good for contests, exams or polls, in which you don't want the users to enter more than one submission. Following are steps to limit your form to only 1 submission per user:
| 1- | Sign in to your FormTitan account. |
| 2- | Enter your form in the form builder. |
| 3- | Open your "Form Properties" > "Settings" > "Limits" Category > Unique submission. |
| 4- | Turn on the "Unique submission" checkbox. Once a user submits the form he will not be able to submit it again. |