mauritius to china ?

hello, Good Day?
As a seafarer on my first contract in 2017 I was required to have a Single-Entry chinese entry permit, but for this my second one my Company informed me that Mauritians and Serbians don't actually need chinese entry permit. I would like to know if I will need a single-entry visa?
If I don't need this time I shouldn't need last time as well. I'm confused that's why I'm asking if I really need one or not? I don't want any issues at the airport.
Thank you for your time and consideration.