Flash using Odin loses sim unlock? SM-N920i

Hi, im experiencing some weird resets when i recieve calls, i reset the note 5 like 3 times and still the same, so i downloaded the NZ rom from Sam Mobile and i was wondering if this phone i bought is sim locked and i flash the new rom i will lose my unlock??
Is there any way to know if my phone is factory unlocked or if its locked whit what company?