I had the same issue but standard troubleshooting (restarts, reinstalls, firewall changes) didn’t fix it. What worked for me was installing an older version after completely uninstalling the current version.
- Thorough Uninstall: Uninstall Postman and delete leftover files from:
C:\Users\<userName>\AppData\RoamingC:\Users\<userName>\AppData\Local\Postman
- Install Older Version
- Disable Auto-Updates: Updating to the latest version brought the problem back.
I used 9.1.5(yes very old) but does the job for me currently, trying a slightly newer, but still older than the latest, version might be worth it. This workaround should help others until Postman releases a fix.