can't get websocket connection working on Apple Watch

I have an app that uses a websocket connection to the Mac on the local network — it works fine on the iphone — it works fine on Apple Watch simulator on a real Apple Watch I get the message

nw_endpoint_flow_failed_with_error [C9403 192.168.0.35:10010 failed parent-flow (unsatisfied (Path was denied by NECP policy), interface: ipsec1, ipv4, ipv6, proxy)] already failing, returning

I can't find any information on that NECP policy and no cure for this error. Please help me

it's Xcode 26.2 and watchOS 26.3 if it matters

can't get websocket connection working on Apple Watch
 
 
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