Sorry for replying so late.
I actually got it to work properly again.
My ISP provides me with the DSL, which I need to tag VLAN ID 7 in order to work. Previously my VDSL-Modem did that and provided the OPNsense Box with the untagged Ethernet network.
I switched this and now the OPNsense Box itself is tagging the WAN network over VLAN 7 and this completely solved my problem.
Thanks for everyones input on this matter. You definitely pushed me in the right direction.
Cheers!
I actually got it to work properly again.
My ISP provides me with the DSL, which I need to tag VLAN ID 7 in order to work. Previously my VDSL-Modem did that and provided the OPNsense Box with the untagged Ethernet network.
I switched this and now the OPNsense Box itself is tagging the WAN network over VLAN 7 and this completely solved my problem.
Thanks for everyones input on this matter. You definitely pushed me in the right direction.
Cheers!