Apple Stores closed in Russia

iPhones can only be repaired in the country where they were purchased. So you will have to take it back to North Macedonia or find a 3rd party store that will fix it, and charge you, because they can’t honor the warranty. While North Macedonia is a candidate for EU membership it is not currently. The EU is considered a single entity for Apple service, so you may be able to take it to a nearby EU member country (Greece, for example) for service.

If the stores in Russia are closed then the stores are closed and you can't get service performed there. You would likely need to take it back to Macedonia if you wanted service.

http://www.apple.com/legal/warranty/products/iphone-english.html

Note this statement from the iPhone and iPad warranty:

"IMPORTANT RESTRICTION FOR iPHONE AND iPAD SERVICE.

Apple may restrict warranty service for iPhone and iPad to the country where Apple or its Authorized Distributors originally sold the device."*

The above is from the USA version of this iPhone, iPad and iPod warranty document, but this particular section limiting international coverage is much the same for the warranty for all countries. If you wish to check the warranty for where you bought your device, click on this link to take you to the page about Apple warranties, then select your device and country --> Legal - Hardware Warranties - Apple

* The EEA (European Economic Area) is considered one country for warranty purposes: Dated 04 01 21 "Apple may restrict service for Apple Watch, iPad and iPhone to the EEA and Switzerland." - http://www.apple.com/uk/legal/statutory-warranty/