DB Connections Error After Upgrade from MySQL v5.7.44 to v8.0.35

I got consistent DB connection error after I upgraded my database instance from version 5.7.44 to 8.0.35. This is the error:

2024-07-06 19:44:56.461 ERROR DBCommand - Error state: 08001 code: 0 Could not create connection to database server. This error is from the appplication reading and writing from the database. Is there any specific reason why the applications are not able to connect to the database after the upgrade to the version 8.0.35.

I used Blue /Green Deployment for my Upgrade/Switchover