Im trying to validate before submitform, this is using a button , onSelect I'm trying to use :
If(IsMatch(User().FullName, DataCardValue3.Selected.DisplayName),Notify("Sorry, you cannot be the submiter. Please select another name"),SubmitForm(SharePointForm1))
but the formula shows an error on SubmitForm(SharePointForm1):

Do you know why?
Is there another way to validate that user().Fullname is not equal to DataCardValue3.Selected.DisplayName ???
Thank you