Is there a way to add a "resubmit" button to allow a user or person filling out a form to change or add infor to an existing form that is being track

Your question: Is there a way to add a "resubmit" button to allow a user or person filling out a form to change or add info to an existing form that is being track

To my understanding, you want your user to have an option to Edit their Submission but the Job Number is still the same. 

Yes, that is possible. As shown in the image you provided, the user need to click the "edit this submission" link to edit their submission and click the Submit button. The Job Number won't change after the editing the submission.

Alternative way, you can provide the "Edit Link" to your user privately. Here's an example of an edit submission link:

https://www.jotform.com/edit/3690324865311956023

You just need the URL (https://www.jotform.com/edit/) and the (submission ID). The submission ID can be found in the Submissions page. Here's how:

Related guide: How-to-View-Form-Submissions

Hope that helps. If I misunderstood your concern, please provide more details about the issue. Thank you.

Can ANYONE who fills out the form have a way to edit or do they have to be a user or subuser?
I'd like the form to be editable by all sales associates so they can change the job as they get more information.
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Anyone with edit link can edit submission. 

You can edit submission from your account or by clicking on edit link option inside of email Notification. 

How to Edit Submissions Made on Your Forms

You can provide your users edit link via Autoresponder email. 

How to Let Users Update Their Form Submissions at a Later Date

Let us know if you need further assistance.