how to change payments method and country/region

Hi,

i'm facing difficulty to change my payments method and country/region . i created my ID in Singapore and i'm originaly from Myanmar. now i move back to Myanmar permently and my debit card from singapore is expire or no money. thus, i want to change my debit card from Myanmar. in this case i need to change country first but in the list of conuntry, Myanmar was not there. also i cannot choose "none" in payment method. please help me to solve this thing.