Unity.Services.Vivox.VivoxApiException: (403)

[satosil]

Some users are unable to login to Vivox with the following error:
Is there anything you can think of as the cause?

[Vivox]: b__0: vx_req_connector_create_t failed: Unity.Services.Vivox.VivoxApiException: (403)
at Unity.Services.Vivox.VxClient.EndIssueRequest (System.IAsyncResult result) [0x00055] in <8d5c1c9233214ae5b084868e2c0879d6>:0
at Unity.Services.Vivox.Client+<>c__DisplayClass24_0.b__0 (System.IAsyncResult ar) [0x00006] in <8d5c1c9233214ae5b084868e2c0879d6>:0
[Vivox]: b__0: BeginGetConnectorHandle failed: Unity.Services.Vivox.VivoxApiException: (403)
at Unity.Services.Vivox.AsyncResult`1[T].get_Result () [0x00008] in <8d5c1c9233214ae5b084868e2c0879d6>:0
at Unity.Services.Vivox.Client.EndGetConnectorHandle (System.IAsyncResult result) [0x00000] in <8d5c1c9233214ae5b084868e2c0879d6>:0
at Unity.Services.Vivox.LoginSession+<>c__DisplayClass110_0.b__0 (System.IAsyncResult ar2) [0x00000] in <8d5c1c9233214ae5b084868e2c0879d6>:0
VivoxApiException: (403)
at Unity.Services.Vivox.LoginSession.b__103_1 (System.IAsyncResult ar) [0x00000] in <8d5c1c9233214ae5b084868e2c0879d6>:0
UnityEngine.DebugLogHandler:Internal_LogException(Exception, Object)
UnityEngine.DebugLogHandler:LogException(Exception, Object)
UnityEngine.Logger:LogException(Exception, Object)
UnityEngine.Debug:LogException(Exception)
Unity.Services.Vivox.d__7:MoveNext()
UnityEngine.SetupCoroutine:InvokeMoveNext(IEnumerator, IntPtr)

[satosil]

It turns out that the cause of the error is the user’s web filtering. However, for security reasons, web filtering cannot be completely disabled and should only allow necessary connections. Where can I find the connection information I need for vivox? The IP listed on the page below is released, but I cannot connect to it.

Vivox: What IPs and ports are required for Vivox (V5) to work?

In addition to the above, the following IPs are also open.
mtu1xp-mim.vivox.com (74.201.103.186)
unity.vivox.com (74.201.103.209)
vivox.services.api.unity.com (34.102.143.233)