Network Connectivity Issue: Roon Server IPv4 Error 502 (ref#C93LVI)

Network Setup

· I use my ISP's router alongside a personal router.

ARC Status

· ARC is *Ready*

Describe the issue

{
"ipv4_connectivity": {"status":"NetworkError","status_code":502,"error":"error code: 502
"},
"external_ip": {"actual_external_ip":"114.aaa.bbb.ccc","actual_external_ipv6":"null","router_external_ip":"null"},
"natpmp_autoconfig": {"status":"NotFound"},
"upnp_autoconfig": {"server_ip":"192.168.50.1","found_upnp":true,"error":"doaction request return statuscode: UnknownError"},
"multinat_autoconfig": {"status":"Failed","error":"Unexpected Error - See Log"}
}

Describe your network setup

ASUS router RT-BE86U