GL-MT300N-V2 no IPv6 on Wifi and LAN

Hey,
I have an small problem. When i am connected with Wifi and LAN then the Devices get not an IPv6 Adress.
On the Interface WAN6 gets the Router my External IPv6 Adress. The Router is able to Ping other External IPv6 Adresses. I Seached in the Web too fix this error but i dont find that what i searched.
Here are my Interfaces:

Thanks Malte.

Hey @Xenic, have you found any solution? I need to use my wifi as WAN however it does not seem to configure IPv6 from the access point.