Claim warranty

As a general rule, the warranty is only valid in the country in which it was purchased. However, there is an exception to this. If you purchased the phone from a country in the European Union, then the warranty is good in other E.U. countries.

An authorized service provider in another country is certainly entitled to ask for your proof of purchase, no matter where you purchased the phone.

There is no such thing as an “international” iphone. The warranty is only valid in the country where the phone was originally sold.

What is the model number displayed in Settings>General>About>Model Number?

You can check the actual warranty status here: Check Your Service and Support Coverage - Apple Support