Hi. 

 I bought this modem with great expectations. From turkey LOCAL DEALER ( TEKNOSA.COM)  Because my modem remained very old. and this modem is exactly 9 times stronger on the paper. but unfortunately I have always made a decision I will be disappointed

because the wifi range is unfortunately very short. It is constantly falling off the internet. For that reason:  It is not possible to watch live broadcast or make leave broadcast on Instagram. It is impossible to watch live streaming on TV. Because it is constantly falling off the internet. I Think, The reason is that the signal quality is very low

However, I have a RE500 router that it can use. RE500 tethering tool  even says that you should approach the modem.It says you're out of coverage.Because  Quality broadcasts cannot be received from this distance.

How can I fix this problem?

many thanks