While working with Microsoft Graph API for Private Chat, my team got this error

Evaluation mode capacity has been exceeded. Use a valid billing model.
Visit https://docs.microsoft.com/en-us/graph/teams-licenses for more details.

The error happens because request to MS Graph exceed the quota per month per app.

Request without model query parameter by default will using evaluation mode:

https://graph.microsoft.com/v1.0/users/[email protected]/chats/getAllMessages

You can see in this documentation to see the quota per app per month for evaluation mode.

To solve the problem, according to this documentation, request to Microsoft Graph must include model query parameter.

https://graph.microsoft.com/v1.0/users/[email protected]/chats/getAllMessages?model=B


https://graph.microsoft.com/v1.0/users/[email protected]/chats/getAllMessages?model=A