Azure Integration - Rate Limits?

When working on a integration
with Azure. Any ideas why the Rate Limits are being applied?

Maybe you hit this limit:

NOTE: Currently, a device can publish at rate of about 1 event/sec, with bursts of up to 4 allowed in 1 second. Back to back burst of 4 messages will take 4 seconds to recover.

Have a look at these limits:
https://docs.particle.io/reference/webhooks/#limits-by-user