Pihole update failed

The issue I am facing:
pihole-FTL not starting after update

Details about my system:
VMware virtual machine running centos 8.5 (just upgraded from 7)

What I have changed since installing Pi-hole:
Went to update Pihole, and was told I needed to upgrade the base OS first. Upgraded centos from 7 to 8.5, then updated pihole and now it shows the following at the end of the update:

[i] Installing latest logrotate script...
[i] Existing logrotate file found. No changes made.
[i] Backing up /etc/dnsmasq.conf to /etc/dnsmasq.conf.old
[✓] man pages installed and database updated
[i] Testing if systemd-resolved is enabled
[i] Systemd-resolved is not enabled
[✓] Restarting lighttpd service...
[✓] Enabling lighttpd service to start on reboot...
[i] Restarting services...
[✓] Enabling pihole-FTL service to start on reboot...
[i] Restarting pihole-FTL service...
Unable to complete update, please contact Pi-hole Support

debug token can be found here - https://tricorder.pi-hole.net/8bljS0mj/

Your debug log shows:

Sep 08 20:02:54 pi-hole pihole-FTL[4069]: /usr/bin/pihole-FTL: /lib64/libc.so.6: version `GLIBC_2.28' not found (required by /usr/bin/pihole-FTL)

suggestions on how to fix that?

This is an old version of the library and recent Operating Systems usually use a newer version, but I don't know if Centos 8 has the correct library.

Maybe you can find a solution reading other comments:
https://discourse.pi-hole.net/search?q=glibc_2.28

Awesome - require an OS that doesnt even support the correct libraries.... sigh and people wonder why I never update my crap.

Looks like its likely time to wipe it clean and start over with a different base OS......

Pi-hole supports Centos Stream 8.
Centos 8 is not supported anymore by Centos/Red Hat.

You can try the docker image.

How did you do that process?