Allow only 1 submission per Email Per Form

1. Navigate to the form you’d like to apply this limitation to

2. Select the field in the form you’d like to use as the ‘duplicate key’ (this is the value that’ll be used to check repeat entries against). In our case, this will be the email field.

3. Within the ‘Field Settings’ on the right hand pane, select the ‘No Duplicates’ option to ensure this field is not allowed to contain duplicates for submissions.