HE.net IPv6 tunnel not working

[ictinc]

Hey there,
While I must be doing something wrong, I'm getting kind of frustrated with OPNsense.
I followed the OPNsense tutorial on setting up a gif interface with tunnelbroker.net.
On my dashboard it seems as though the IPv6 gateway is online.
However when I try to do a DNS lookup from the OPNsense interface all DNS servers are giving results except for the configured external IPv6 DNS servers.
I've created rules on both the WAN and the GIF interface stating to allow any outbound DNS traffic without any luck.
Also when I do a traceroute from the interface to the external IPv6 DNS server and leave the source address to default I receive "no route to host". This also happens when I change source address to WAN or the GIF interface.

Any help would be much appreciated.

Kind regards..