Lost previous submissions to a question when I deleted a field on form

Hello!

Please help. I lost all the data to a field I most recently deleted. I didn't know I would lose ALL the data from that previous question.

Is there any way I can retrieve that data back?

When a field is deleted that has submission data, there should be a pop-up stating that data associated with that field will be removed if the field is deleted.  In any case, if you restore your form to a previous save point before the field was deleted:

https://www.jotform.com/help/294-How-to-view-form-revision-history

The data should also be restored for that field.