ASG 220 - no internet access after upgrade to 7.5 (from 7.304)

Dear Astaro-Friends,

Unfortunately, we have the following problem:

We used to run 2 Astaro Appliances ASG 220 in HA Modus (Firmware 7.304).
Everything was perfect, network, internet, vpn, etc.

Now, we did an upgrade with one of the two appliances to firmware 7.5, which have been installed successfully. Also the config file has been installed without any problem.

When we took the new upgraded ASG220 with version 7.5 in our network, the internet connection did not work anymore and we do not know why (we have a "company connect"- connection by the German Telekom).

Therefore I needed to take the "old" ASG220 with 7.304 in the network again to be able to use the internet.

Unfortunately, I could not find the error why no internet connection is possible with the new firmware 7.5.

I would be pleased if somebody has an idea.

Thank you.

Best regards, Erik (Lost in EDV)