Webauthn server implementation in a microservices architecture

I have a problem with retrieving the RP informations (name and id) that's because the RP request goes to the gateway first then to another service in which the request is treated and formatted to be sent to the webauthn service, to resolve this issue i started using the Referer header to get the rp id, and i was wondering if this was good practice or maybe if you guys have a better work around.

I appreciate all the help you guys can provide.