I bought Samsung Galaxy A5 2017 (SM-A520K) when I was in Korea. The device worked fine in Korea. I used wifi connection in Korea and it worked fine. No problem was there. But when I brought the device in my country (Bangladesh), it could not connect to any wifi. My wifi connection is OK, other devices working very fine, except A5. The device does not have any other issue, only it does not connect to the wifi. What should I do?