Hey @subhan,
This issue only happens with localhost urls. To solve this you could use https://ngrok.com/ to turn your localhost server into a free server with a url, and replace the localhost redirect url with the ngrok url.
Instead of http://localhost:8080/api/v1/zoom/complete-oauth it would be
https://d4c4477b.ngrok.io/api/v1/zoom/complete-oauth
This way you can still develop and test locally and have your redirect url work!
Let me know if this helps!