I recently switched to Jio Fiber. I have a house with a lot of walls due to which there were some Wifi dead zones. So, I used to use an RE305 Range Extender with my previous ISP. 

When I switched to Jio, I did reconfigure to the new network and the extender worked fine for a day or two. But one fine night, there was a fluctuation in the main network and the extender switched off for a while. 

Now, no matter what I try, I am not able to extend the Wifi range. PS: I was extending it wirelessly. Not as an AP.

Problem: 
 

1. I can go through the set up steps, give the password for the 2.4GHz signal and on the final step, the set up says it's done but the "Signal" and "2.4GHz" light just never turns on. 
2. Consequentially, any device can't even recognize the extended network.

Troubleshooting steps tried: 

1. I tried resetting the repeater and set it up from scratch.
2. I tried the WPS paring as well.
3. The 5GHz source network is not being recognized on RE305. But I know this is because of the channel on which my Jio router is transmitting the 5GHz signal. It's on 149 which I know isn't supported by RE305. But this is not even my concern.
4. The router is transmitting the 2.4GHz on channel 6
5. I have tried rebooting the router multiple times.
6. I have reset the repeater multiple times.

None of the troubleshooting gets me past the last step where the "Signal" and "2.4GHz" lights turn on and I am not able to even find the extended network.