Error type: "Forbidden". Error message: "The calling IP address 2a02:348:5e6:1::e3f does not match the IP restrictions configured on the API key. Please use the API Console to update your key restrictions." Domain: "usageLimits". Reason: "ipRefererBlocked".

Did you added your own Google API key? Look at the help.

Check in YouTube if the id StalvanStokkom belongs to a username. Check the FAQ of the plugin or send error messages to support.