How to pass the cookie to form

Your software
My Mautic version is: 2.15.2
My PHP version is: 7.2.22

Your problem
My problem is: Mautic creates one anonymous contact and one identified that is not tracked.
The problem is that we need to know how to pass the cookie over to a 3rd party form?

These errors are showing in the log: N/A

Did you ever get this problem resolved?