SOLVED !!! By using extension cable ( about 70 cm ) between modem and router it connectes. The problem was interference between modem and router . Thanks John K and Wahroonga Farm for their valuable...

Thanks for suggestion . I have tested it while AC power is plugged and on . Unfortunately nothing has changed . The device connects 3G if the signal is powerful . So the problem is associated with...

Region : Others Model : TL-MR3040 Hardware Version : Firmware Version : ISP : The connection problem of TL-MR3040 has been identified , it is signal level . Although I am sure all the ISP setup...