Do you have an add-on called “Pay-per-use Intl LD”? Or if not are you able to add it?

Hi ​@SteveE, what line are you trying to use to make the call? If you can confirm the last 2 digits of the phone number we can check if the line is provisioned for international calling. 

Also, please note pay per use calls to Mexico are $1.80/minute. You can check rates and add-ons here https://www.koodomobile.com/en/help/long-distance-calling

#7693.....as #1790 works fine.

Ok ​@SteveE, I’ve added the International Pay Per Use feature to your 7693 line, please restart your phone and test when you get a chance. International calling should now work.