Why is Google Docs integration is overwriting submissions?

When new people submit a submission using our jot form it is overwriting the previous submission instead of adding the record to the  document. It worked until June and now as each person completes the form it adds the person to record number 2 and overwrites the previous person in the form as record 2.

Please let me know how we can fix this issue.

I checked the Google Spreadsheet integration and it is working properly on my end. Please try re-integrating the Google Spreadsheet again to your form. To do that, please follow this guide: https://www.jotform.com/help/228-How-to-Integrate-Form-with-Google-Spreadsheet

Also, I have cleared your form cache from our server so it will be refreshed. 

Please give it a try and let us know how it goes. Thank you.

I had tried to sort the document by last name and that is when it fell apart. It is working correctly now. Is there anyway to set it up so it will sort by last name instead of submission date?Thanks,Jennifer
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Dear Jennifer, 

The submissions will be sorted by the submission date, automatically. However, if you click on the arrow on the header, you will be able to sort them as you wish as you can see the screenshot of a spreadsheet below:

I hope this helps.

Thanks.