No access to internet from blue network

Hi all
Since I have updated to IPFire 2.29 - Core Update 186 I am not anymore able do connect to the internet from the blue network. From the green network it is always possible. I have for both networks the same rules that allow access to the internet. Before this update all worked without issues. In the logs I do not see any drop from blue to red. Within the blue network everything works as it should.
Also, with the latest version I have the same problem.
All clients on the blue network recive a dhcp lease. I also did a restore to a backup from the beginning of the year, I can’t always not access the internet from blue.

Regards
Andy