First lets check date/time.
Whats output for below two?
timedatectl
timedatectl timesync-status
If date/time is incorrect and want to change, you have to disable NTP time syncing first with below:
sudo timedatectl set-ntp 0
Set the time manually (change date/time below to actual):
sudo timedatectl set-time '2021-06-24 03:50:00'
Enable time sync again:
sudo timedatectl set-ntp 1
And verify:
timedatectl
A very long thread below with hints how to diagnose unbound:
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