The background to this requirement is interesting. They are not accepting just the sports authority certification any more they want the sports authority to individually write a letter for each customer.
It's a crazy requirement they may as well ask for a letter from the king .
I dare nor say more but my gym now don't support Cambodia as a viable destination due to this despite having every gym license available
Sports authority
Board of boxing sport A License
Ministry of education instructors
But going down the sports authority and getting personal letters is not happening