If you would like to provide your customers a link which gives pre populated form fields for your return portal this can be done easily.
Please find example below which will help you pre populate your return portal for customers.
returns?email=support@clicksit.com&id=1234
Example with domain
https://greatcollection.co/a/returns?email=support@clicksit.com&id=1234
Any questions just get in touch