Microsoft Graph API - /sendMail and /messages endpoints returning 500 error

In Python where "shared_email_address" is an email address to which access has already been configured. This code has been working for months on end, but started to hit the 500 error on 8/31/2026, so I want to determine if there are any known outages or changes that have been made to these endpoints. Additionally other endpoints (outside of mail/message endpoints) are working.

import msal
import requests

tenant_id = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" # id of my tenant
client_id = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" # client_id of my app
shared_email_address = "******@company.com" # shared email address of my department 

app = msal.ConfidentialClientApplication(
                    client_id=client_id, 
                    client_credential=None, 
          			authority=f"https://login.microsoftonline.com/{tenant_id}"
                )

token = app.acquire_token_for_client(
	["https://graph.microsoft.com/.default"]
)

headers = {
            "Content-Type": "application/json",
            "Authorization": f"Bearer {token}",
        }


resp = requests.get(
	url=f"https://graph.microsoft.com/v1.0/users/{shared_email_address}/messages", 
	headers=self.headers
)
# Returns 500 error