NZB Indexer Connection Issue

[Parabellum82 0]

I switched from Nord to AirVPN recently for the port forwarding ability. Everything is working great except that Radarr and Sonarr (both are Docker containers in Synology NAS) can no longer connect to my two NZB indexers, nzbfinder.ws and nzb.life. If I remove VPN or switch back to Nord on the NAS, they immediately start working again, so it's not the settings or API key. I get the following error in the log as soon as AirVPN connects (same every time for several weeks):

Unable to connect to indexer: Resource temporarily unavailable (nzbfinder.ws:443)
System.Net.Http.HttpRequestException: Resource temporarily unavailable (nzbfinder.ws:443)
 ---> System.Net.Sockets.SocketException (11): Resource temporarily unavailable
   at System.Net.Sockets.Socket.AwaitableSocketAsyncEventArgs.ThrowException(SocketError error, CancellationToken cancellationToken)
   at System.Net.Sockets.Socket.AwaitableSocketAsyncEventArgs.System.Threading.Tasks.Sources.IValueTaskSource.GetResult(Int16 token)
   at System.Net.Sockets.Socket.<ConnectAsync>g__WaitForConnectWithCancellation|277_0(AwaitableSocketAsyncEventArgs saea, ValueTask connectTask, CancellationToken cancellationToken)
   at NzbDrone.Common.Http.Dispatchers.ManagedHttpDispatcher.attemptConnection(AddressFamily addressFamily, SocketsHttpConnectionContext context, CancellationToken cancellationToken) in ./Radarr.Common/Http/Dispatchers/ManagedHttpDispatcher.cs:line 337
   at NzbDrone.Common.Http.Dispatchers.ManagedHttpDispatcher.onConnect(SocketsHttpConnectionContext context, CancellationToken cancellationToken) in ./Radarr.Common/Http/Dispatchers/ManagedHttpDispatcher.cs:line 313
   at System.Net.Http.HttpConnectionPool.ConnectToTcpHostAsync(String host, Int32 port, HttpRequestMessage initialRequest, Boolean async, CancellationToken cancellationToken)
   --- End of inner exception stack trace ---

Any troubleshooting guidance or advice would be appreciated. Thanks.  Edited ... by Parabellum82
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