There are so many ways or methods by which you can quickly fix or resolve the Wavlink WiFi range repeater issue. 

Improve Software Of Wavlink AC1200 Repeater

To improve the software of the Wavlink AC1200 repeater device you will need to visit the Wavlink web management window. From there click on the network advanced option and then choose the firmware upgrade. Now, if you see the latest version of a software file then install it on your computer or laptop. In the end, restart the Wavlink AC1200 repeater to improve the software. 

Power Cycle Wavlink Repeater

Press the power button of the repeater to turn off the device. After that, take out the AC1200 repeater power plug from the socket. Next, wait for some while and place the power plug of the AC1200 repeater back in the socket. In the end, press the power button to turn on the device. 

Reset Wavlink AC1200 Repeater 

At the bottom or back of the Wavlink AC1200 repeater, you see the reset button. Press the reset button for 10 seconds by inserting the hairpin in it. Now, all the Wavlink repeater LEDs will be turned off. Thus it means the Wavlink repeater device is now completely reset. 

Note: After resetting the Wavlink repeater, do the Wavlink AC1200 repeater setup procedure again.