Connectivity problem with Orbi and Arc

Roon Core Machine

Intel NUC10i7FNH running Rock Version 2.0 (build 1223) ; 500Gb SSD 8Gb Ram

Networking Gear & Setup Details

Draytek Vigor 130 feeding Netgear Orbi RBR50 router

  1. Who is your internet service provider?
    Vodafone

  2. Please list the make and model of your modem and router?
    Netgear Orbi RBR50

  3. Do you have any additional network hardware, like additional routers or managed switches?

  4. Does your network have any VPNs, proxy servers, or enterprise-grade security?
    No

Connected Audio Devices

NUC is connected directly to Orbi Router via Cat 6 Ethernet cable.

Description of Issue -

What is the exact port forwarding error message you see in the Roon Settings → ARC tab?

I cannot connect to Arc outside of the house (via 3/4/5G). I have followed the manual port forwarding instructions to the letter and still wont’t connect.
Before I tried the manual port I got the following error messages from the Roon setup page :
ipv4_connectivity": {“status”:“NetworkError”,“status_code”:504,“error”:“error: Error: ETIMEDOUT, response code: undefined, body: undefined connected? undefined”},
“external_ip”: {“actual_external_ip”:“90.aaa.bbb.ccc”,“actual_external_ipv6”:“null”,“router_external_ip”:“null”},
“natpmp_autoconfig”: {“status”:“NotFound”},
“upnp_autoconfig”: {“server_ip”:“192.168.1.1”,“found_upnp”:true,“error”:“Did not find UPnP service with WANIPConnection on network”}
}

When I try the manual port forwarding ….all the error message disappears …but still says it cannot connect (& loses the IP Address).

Any help would be much appreciated