How do I 'permanently' delete rows from a Google Spreadsheet?

I have a jotform with integrated spreadsheets.  I did a couple of test runs when I made some changes to the form. Now however, those tests (the input from the form) are mixed into my spreadsheet.  I can't seem to get rid of it.  I can delete the unwanted rows but every time there is a new submission, they reappear.  Is there a way to "permanently" delete these tests from the spreadsheet? They are very much out of place and interrupting my data. I appreciate any help.  Thank you in advance!  

Thank you for contacting us.

Can you please first delete the form entries from a form Submissions page?

Then, you can delete these rows from the Google Spreadsheet. I hope it will fix the issue.

Please give it a try and let us know if you need any further assistance.