Please follow the below template, it will help us to help you!
Expected Behaviour:
pi-hole updated
Actual Behaviour:
[✗] Update local cache of available packages
Error: Unable to update package cache. Please try "apt-get update"
Unable to complete update, please contact Pi-hole Support
pi@pihole:~ $ apt-get update
Reading package lists... Done
E: Could not open lock file /var/lib/apt/lists/lock - open (13: Permission denied)
E: Unable to lock directory /var/lib/apt/lists/
W: Problem unlinking the file /var/cache/apt/pkgcache.bin - RemoveCaches (13: Permission denied)
W: Problem unlinking the file /var/cache/apt/srcpkgcache.bin - RemoveCaches (13: Permission denied)
pi@pihole:~ $
[I apologize for my novice understanding. Here is what happened next.]
pi@pihole:~ $ sudo apt-get update
Hit:1 http://archive.raspberrypi.org/debian buster InRelease
Get:2 http://raspbian.raspberrypi.org/raspbian buster InRelease [15.0 kB]
Reading package lists... Done
E: Repository 'http://raspbian.raspberrypi.org/raspbian buster InRelease' changed its 'Suite' value from 'stable' to 'oldstable'
N: This must be accepted explicitly before updates for this repository can be applied. See apt-secure(8) manpage for details.