Azure Flow Egress IP Addresses

I am trying to access the API from Azure using flow. I can access fine using my test tool locally. Azure fails with a 403 error. I suspect the issues re due to the firewall and now allowing connections from Azure.

The outbound IP ranges are listed as below for the UK.

51.140.148.0 - 51.140.148.15, 51.140.80.51, 51.140.211.0 - 51.140.211.15, 51.141.47.105

Can these be added ? I can not add ranges or any more than 5 IPs.