When a user submits a form, it may not always be clear that it has submitted successfully. This can be very confusing for the user and may result in them attempting to submit the form again. It is important therefore to provide clear feedback letting the user know that their information has been successfully submitted.
Once a form has been submitted, provide a clear message that conveys this to the user. It can be as simple as a response saying "Thank you for submitting the form!", or "Submission successful! We'll be in touch soon." or whatever is suitable.
No example is available.