Problems with google sheet

Someone submitted a form twice accidentally. I went to submissions and deleted the second form. When I look at google sheets, the submission is still on the spreadsheet.

Please note that the submissions will not be deleted from the Sheet when they are deleted in the form's submissions page. 

You can delete the duplicate submission from the Sheet by using the delete row option. Editing of the Sheet that is integrated with a form can break the integration. However, based on my tests deleting a row will not break it. 

Another option is to re-integrate your form with the Google Sheet.