looks like the module uses nginx for it’s webserver…so i presume your either accessing it tcp:80 or tcp:443
so you need to configure nginx to a different port, but that will move everything , all you virtual hosts etc etc etc.
I guess the answer is to spawn another nginx server just for the service, but currently nixos can’t do that by default.
Hopefully in the future nixos will be able to deploy ‘instances’ of each service.