TP-LINK is not a good company at all. They do not give support for their product.

I had the same problem and upgrade the firmware to the beta version and everything worked flawlessly except the range is not good enough. My region is Bangladesh. I wish someone could help you...

Dear Mavis, Thank you very much. You saved my day.

Dear @Vik Where can I get the beta firmware? I am also having the same issue. I recently bought the router but the bandwidth controller is not working which is my number 1 priority as my internet...