Do you have different network providers to choose from in your location (which country?)? If so, try others!

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….keep on rockin' 🤘🏼🤘🏼🤘🏼

Do you choose the numbers in international format?

+4179 etc

Try it manually and not from the contact list and if you have the advanced calling functions in there, then take them out just to try.

Good luck

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