I ran your script verify_time.sh and saw NTP synchronized: no !
Consequently I concluded that my NTP install operation followed by another chrony install introduced some issue.
Thus I apt-get removed chrony and tried to install it again.
However new install failed until I used the following parameter in order to remove ALL chrnoy related files :
apt-get purge chrony
before install it again with success.
Then your script showed me that NTP was synchronized.
Many thanks for your help.