OK, Do you have your firewall activated? Do you have access to F-Droid on your phone? I was going to suggest removing Zorin Connect, but read on other posts awhile back it is no longer available on PlayStore. Try removing the entries to your computer from Zorin Connect on your smartphone. Next if not activated, start the firewall and add the preset rule of allowing Zorin Connect to run through the firewall.
See my tutorial here:
If you still have issues after this I would recommend KDEconnect, as it has always worked for me. The firewall also contains a rule for KDEconnect.