No IPv6 access when firewall is turned on

[Keyinator]

Today I added an ipv6 adress to my proxmox instance. However, I found out that pinging the ipv6-ip only works with disabled firewall.
I have attached the firewall rules and the network-config. Any ideas what could cause this / how to fix it?

Datacenter:


Node:



Networking:

 

[eXtremeSHOk]

Did you ever find the cause for the above or a solution ?