Q: Hello. I bought iPhone SE in NYC this

Return to the store in New York and talk to the manager or find a cell provider where you are that uses the LTE bands in that model.

Take it to your local Apple vendor and see if you can purchase a replacement. It is not the seller's responsibility to tell you anything that you don't ask about. If you don't know what to check, then you are simply a sucker waiting to be taken or to be a victim of your own ignorance. Sounds like the latter applies in this instance.

No one is going to be able to help you and there isn't a thing you can do if your local store won't help you out.

Have you put in a SIM from your local cellular provider? It won't work without one.

Or you can try Kappy's suggestion, or you can try checking with other cell provider's in your area to see if they use the LTE bands you need.

I would not have trusted that an Apple Store employee in NYC would be knowledgeable and familiar with carrier features and frequencies in Russia. You should have checked the phone specs yourself online beforehand and made sure your carriers network would be supported.

It is not reasonable to expect a store employee to know about carrier specific features in a foreign country. This is also one of the reasons why many people here always recommend buying an iPhone in the country you intend to use it in, and to get your service from a carrier who officially supports the iPhone.

This support site is not Apple, you are speaking with volunteers here.

Contact apple using the link at the bottom of this page and ask to file a complaint with the Apple Store that the rep give you erronious information and you purchased the phone based on that information.

No, I don't expect Apple employees in one country to be informed and knowledgeable about carrier's and network features in other countries. I would have researched that myself. The information is easily found right here on apple's web site under the device specifications and the LTE coverage features for each iPhone model.

You chose to purchase your iPhone from a foreign country to that which you intended to use it in.  Expecting a store employee in a store half a globe away to know what you needed for your local carrier in another country is simply not reasonable, IMO.