iPhone adds North American country code to Estonian phone number

I got my first iPhone in the US, with a US number, and created my Apple account in the US. From that US phone number I WhatsApp and texted an Estonian phone number. No issues with that. This Estonian phone number belongs to my now wife, and is the only Estonian phone number I texted from my US number.

Fast forward some years... I moved to Estonia, bought an iPhone in Estonia with an Estonian phone number. I can call my wife with no issues, but when I text her the iPhone is adding 011 in front of her full Estonian number - country code +372.

It was confirmed by my carrier in Estonia that when I call my wife the phone is sending just her Estonian number, but when I text the phone is appending her full Estonian number with 011. And of course the text doesn't go through.

I need to be able to text my wife. I called Apple support ant they were pretty useless.