@Navdeep Hello, 

Thank you for your detailed information. From the photo RE did not connect to router's WiFi yet. 

If only power leds lights up after you set up RE, please  try suggestions here: 

1>Please verify your Wi-Fi password by forgetting your Wi-Fi network on cell phone first :  
Go to Settings-> WiFi on your phone, Tap (or Long press  the router's WiFi name  ->Forget / Delete the network 
Please reconnect to your router wifi and it will ask for a password, will it accept your router password?

2> factory reset tp-link range extender : press the reset hole for 10 secs with RE powered on
On cell phone Wi-Fi settings, connect to Range extender WiFi first ( do not connect to router wifi or and turn off mobile data)

3> Put RE close to router and follow instructions on Tether app or Web page step by step to set up RE again  ( carefully examine the Wi-Fi password you have put in, and it is recommended to create a different SSID/WiFi name for RE )

Please also make sure Bell home hub does not have any Advanced settings that may affect RE, like access control, whitelist, mac filtering. 
If the above does not work, after set up, can you login to RE's web page, go to Settings--system-- system log, save the log file and sent to us. Thank you