Unconvert a Job back to a Quote
Open the find jobs window and click on the Ellipsis → Delete on the desired Job

On the Find Quote screen uncheck the Active only box and your quote should show in the list.
Double click on your quote or click on the Ellipsis → Open Quote

Go to the ‘Add’l Info’ tab, find the ‘Converted To Job field, click on the Ellipsis → Unlink from Job.

Click ‘Unlink’ on the prompt to confirm your decision

Click the ‘Active’ checkbox at the top of the quote and you will be good to go.
