Hi, I was just wondering if there is any specific reason for Serbia having abbreviation SR?

According to the ISO specification Serbia has two character abbreviation of RS (which I know is strange but is apparently correct https://en.wikipedia.org/wiki/Country_codes_of_Serbia) as SR stands for Suriname.

https://www.iso.org/obp/ui/#iso:code:3166:RS
https://www.iso.org/obp/ui/#iso:code:3166:SR