Work with PHP and now no-one can login

I have had on my to-do list to get nextcloud using php7.4 as it currently uses 7.2 and I can not figure out how to move up to 7.4.

I have tried many different things today and each one failed in a different way so I have put it back to the way it was. I did this 4 to 6 times and it worked. I would log in and everything was fine but still on 7.2.

The last thing I did was install php-redis and php-apcu without putting the version in. The server came up but when I try to login with the same password that I have 6 plus times today it says I have the wrong password. I uninstalled php-redis and php-apce and installed the 7.2 versions back and still have the same issue. I know the password is correct. Any pointers on seeing what the disconnect is?

When I have looked at the log files I do not see anything that are showing any login failure.

Can someone step me through how the login process works and where I would possibly see the problem that is causing my nextcould to fail?

Nextcloud version (eg, 20.0.5): 20.0.5
Operating system and version (eg, Ubuntu 20.04): Ubuntu 1804
Apache or nginx version : Apache 2.4.29
PHP version (eg, 7.4): 7.2 trying to go to 7,4

I was able to get it back and going. How this happened was I changed the /etc/apache2/sites-available/nextcould*.conf to use the 7.4 version and then restarted apachy2 and now it is working again. This time I am going to make a VMware Snapshot before messing with it again.