Did you "Choose Your Own" Verification Settings?
When defining Verification Settings for Origin SSL Certificate Verification, you can select "Choose Your Own." This lets you to control exactly which certificates or certificate authorities our Edge servers should trust when securely connecting with your origin.
If you've selected this method, you need to configure the Trust setting to conform with how you set up your origin certificate.
|Origin Certificate Method||Trust Setting|
|Method 1: Use a publicly trusted certificate authority||Akamai-managed Certificate Authorities Sets|
|Method 2: Specify a certificate authority||Custom Certificate Authority Set|
|Method 3: Pin a specific certificate||Specific Certificates (pinning)|