Old Navy Gift Card code can only be used in the country it is issued for.
You can contact the Old Navy customer service here https://oldnavy.gap.com/customerService/info.do?cid=3171&mlink=5151
This eGiftCard is issued by and represents an obligation of Direct Consumer Services (“DCS”). The eGiftCard may be redeemed for merchandise at any Old Navy, Old Navy, Old Navy, or Athleta location, including Outlet and Factory stores. The eGiftCard may also be redeemed online for merchandise at Old Navy.com, oldnavy.com, bananarepublic.com, athleta.com, or hillcity.com. If you return merchandise originally purchased with an eGiftCard, any refund will be issued in the form of a plastic gift card issued by DCS which may be used at any of these stores or websites. Any merchandise purchased with an eGiftCard is subject to the applicable store or online return policies. Purchases will be deducted from the amount of this eGiftCard until the value reaches zero. This eGiftCard may not be used or redeemed with certain promotional offers and may not be applied as payment on any account. You may not use an eGiftCard to purchase other eGiftCards. Additional value may be added to this eGiftCard at any Old Navy, Old Navy, Old Navy or Athleta store. Redeemable for cash when the balance is less than $5 or as otherwise required by law. Restricted to use in the USA, Puerto Rico and Canada. By purchasing this eGiftCard, you agree that the laws of the State of California, without regard to principles of conflict of laws, will govern this Agreement. Limit 5 eGiftCards redeemable per online transaction.