0255 is not a country code. Numbers inside a country start like this: Spitak, Lori (Armenia), IJmuiden (Netherlands), Caraș-Severin (Romania), Portuguesa (Venezuela) and others. The first digit 0 is the trunk prefix for domestic calls and is dropped from abroad.
Have the full number? Check it in the number lookup.
| Area or operator | From abroad | Inside the country |
|---|---|---|
 Spitak, Lori · Armenia | +374 255 … | 0255 … |
 IJmuiden · Netherlands | +31 255 … | 0255 … |
 Caraș-Severin · Romania | +40 255 … | 0255 … |
 Portuguesa · Venezuela | +58 255 … | 0255 … |
 Quang Ngai Province · Vietnam | +84 255 … | 0255 … |
If a number starts with +, the first 1–3 digits are the country code. If it starts with 0 (8 in Russia and Kazakhstan), it is a domestic number: an area or operator code follows, and from abroad the 0 or 8 is replaced with + and the country code. The same digits can mean different places, so where the call came from matters.