Can't view Sling streaming app

Hope this is in the right place. I have used Sling app for over a year, but last Monday I could not use it due to an error message of “You have been signed out because an attempt was made to access the application outside of the United States. [10-51]”

After numerous reboots, app deletion and reinstalls, router reset, many “Chats” with Sling Tech Support I cannot even sign in to my account.

Sling comment: With the type of error you’re getting, this is usually happening when Sling could not verify your streaming location.

My question: How can I verify?

Sling: VPN’s are the primary causes since they can alter your approximate location on the internet and Sling ony work in the US.

My comment: Understand, but the Cox Internet data should verify my location

Sling: I understand. I do not have the specifics of the issue other than what usually cause it that’s why I escalated it to the developers.

Hopefully this is just a simple tweak someplace. Can you help?

The reason Sling tech finally said about VPN is that last Sunday I watched part of a ball game on a public open WiFi signal. (A Scottsdale Public Park) Maybe the park used a VPN? Could that have caused the issue?