Unable to Save Tab Configuration in Teams Meetings

Hello,

Over the past few days, I have been unable to add any apps during a meeting in Microsoft Teams. I have tested this with multiple apps, and each time I receive the following message: “Unable to save {APPName} tab configuration.”

I have attempted this both in the Teams desktop application and in the browser version, but the issue persists in both.

When checking the browser’s developer tools (Network tab), I noticed that the related request consistently returns a 500 error code:

https://teams.microsoft.com/api/chatsvc/emea/v1/threads/{XXX}/properties?name={XXX}

{
    "errorCode": 500,
    "message": "{\"subCode\":\"TabOperationFailed\",\"details\":\"Initiator 8:orgid:{XXX} failed perform tab operation\",\"errorCode\":1500,\"errorSubCode\":null}",
    "standardizedError": {
        "errorCode": 1500,
        "errorSubCode": 1,
        "errorDescription": "TabOperationFailed-Initiator 8:orgid:{XXX} failed perform tab operation"
    }
}

Any assistance in resolving this would be greatly appreciated.