Istore account Balance zeroing

I want change my Istore to Oman store because I already transferred from UAE and. Want to add my visa and and recharge my Istore account but I still have few of AED on my Istore account therefore I didn’t can change my Istore country because my account should be zero to allow to me change to other country and this amount of money little than any purchase action In market 1.56 AED therefore I can’t spent, I ask you to make my account balance zero that allow to me achieve my goal, please help me as soon as possible .