Hi @Anonymous
Thanks for visiting our forum. Microsoft Teams tag is mainly focused on the general issue of Microsoft Teams application troubleshooting. Based on your description, this problem is more related to Microsoft Graph, which we're not familiar.
The following is for informational purposes only:
According to the Microsoft Graph document, the following limits apply to sending 1-to-1 messages using the MS Graph API:
The limits apply to any request, including POST requests that send a message. However, these limits are subject to change and may vary depending on the request type, the scope of the limit, and other factors.
Hope the above information is helpful for you!
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