I ran a ssl server test against api.opsgenie.com from ssllabs.com and noticed the certificate is valid from 18 Mar 2019 which suggests they recently renewed the certificate. I also notice they only support TLS 1.2. My guess is they removed support for older security protocols around the time they installed the new certificate.


Is Tls12 listed if you run [Net.ServicePointManager]::SecurityProtocol in PowerShell?

You could force PowerShell to use Tls12 by running the following before you run Invoke-RestMethod.

[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12