OnSessionTokenRequired callback not triggered in .NET SDK v4.1.1 (similar issue found in JS SDK)

[Chanhun]

[Problem/Question]
The OnSessionTokenRequired callback was not triggered when the session token expired in the .NET SDK (v4.1.1).
We have confirmed a similar issue existed and was resolved in the JavaScript SDK, suggesting a possible related cause.

[SDK Version]
.NET SDK v4.1.1 (used in .NET Framework 4.8 WPF)

[Reproduction Steps]

1. Call SendbirdChat.Init(…)

2. Register SendbirdChat.SetSessionHandler(…)

3. Call SendbirdChat.Connect(userId, sessionToken, …)

4. Wait until the session token expires

5. The OnSessionTokenRequired callback is expected but never called

6. Meanwhile, the OnSessionError callback is called when the session expires

[Frequency]
Occurs every time. (OnSessionTokenRequired is never called)

[Current impact]
Automatic session token renewal does not work, so after session expiration, the client must reconnect by calling Connect again to resume normal operation.

[Additional Notes]
A similar issue was confirmed to have existed and been resolved in the JavaScript SDK:

Session handlers not being called

I tried setting up the session handlers following this guide Authentication | Chat JavaScript SDK | Sendbird Docs The session handler is set up before opening the connection as instructed in the documentation. The scenario that I want to handle is when a session token is expired or revoked, so I could request for a new session token and call onSuccess in the onSessionTokenRequired handler. Currently none of the events are triggered when I revoke the token, or when I purposely issue a short-li…

Please verify if a similar internal trigger omission exists in the .NET SDK.

[Chanhun]

I’ve confirmed that it’s working normally. Was it modified on the backend? Thank you.