Ubuntu 20.04 login loop with fail to raise network interface issue

I am not so expert but comfortable with Linux use, I had an issue of loop login that popped up after a restart–done due to freezing of screen on the remote desktop session of turbo VNC on the version 18.04 bionic, I tried to fix it with the general https://disneyhubs.com suggestion of rebooting a couple of time and change of some network rule file but failed and finally upgraded to 20.04 with hope to fix with an update but failed. Please help...