It seems like a lot of people are having the same issue so it's likely on Microsoft's side.
https://answers.splunk.com/answers/779459/microsoft-office-365-reporting-add-on-for-splunk-i-2.html
https://answers.splunk.com/answers/780097/microsoft-office-365-reporting-add-on-for-splunk-n.html
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Installing and validating permissions for splunklib will resolve "No module named splunklib.client"
Opening TCP/5671 to Azure on the firewall will resolve "Modular input azure_diagnostic_logs://AMDL No connection on hub: insights-logs-alerts. Is there a network route to the endpoint?"
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