Our Zabbix server version and front end version are 7.0.2. For the last couple of months, I keep seeing the message "New update available" but when I try to install updates for Zabbix, I always get these errors:

xxxxx@rbb-dclnx0q1:~$ sudo apt-get install --only-upgrade zabbix-server-mysql zabbix-frontend-php zabbix-agent zabbix-agent2
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
E: Unable to locate package zabbix-agent2

xxxxx@rbb-dclnx0q1:~$ sudo apt install --only-upgrade 'zabbix.*'
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
E: Unable to locate package zabbix.*
E: Couldn't find any package by glob 'zabbix.*'

I have followed the upgrade guide in this link but could not get Zabbix to upgrade either.

https://www.zabbix.com/documentation/7.0/en/manual/installation/upgrade/packages/debian_ubuntu

Please advise. Thanks.