@vpnmylove 

Hi, thanks for posting question here.

As I know, it seems there is no factory reset option on Web UI or Tether App. May I confirm the "reset" you mentioned is reboot actually?

It is suggested to take factory reset on the router via the reset button(hole)(Press and hold the button until all LEDs turn on to reset the router to its factory default settings.) and reconfigure it to check the performance.

If it is the same problem, please follow this guide to troubleshoot. You may also contact local support for direct help.