@Gopa 

Hi! I was facing the same problem and after applying this recommendation, I was able to scan and connect to my 5Ghz ntwk. Hope this helps: https://www.tp-link.com/ae/support/faq/1314/

@prado Thanks. Let me try. Will update if this worked

I have a Reliance Jio fibre connection with dual band router 2.4Ghz and 5Ghz bands. I also have TP-link AC1200 Mesh Wifi range extender however, exxtender just shows the 2.4Ghz network during scanning, and its does not shows 5Ghz network only. Initial at veryt time it got connected but when i switch off and ON the extender then it does not  scan 5Ghz band. Could someone please let me know the solutoin for the same.

@Solla-topee 

Yes, Model number of my range extender is RE300
Model number of home router is - Jio Fibre router. No model no given on the router
Not sure how to change the channel for 5ghz channel on the home router to be channel 36/48. if you can guide me then would be helpful.
Extender is able to scan my host router 5ghz but if i switch off the extender and when i again switch on the extender then extender does not scan my my host router 5ghz. To have my extender scan the host router 5ghz i have to reset my extender and then when i again scan then sometimes the host router 5ghz appears.

If you can provide me with  teh solution then it would be helpful.

@Gopa I am using TPlink RE305 extender. I am facing the same problem. TPLink extender does not detect the JIO routers 5G band. Earlier i had airtels Nokia router and i had no problem with that. But when i migrated to JIO, the TP link extender (RE305) is not able to detect 5G wifi network. Jio's 2.4Ghz network is working fine.

Pls suggect if theer is any solution for this

@MohanPoojary 

Was there any resolution to this issue from TP links side? I just bought an extender today and frustrated that it does not scan for my 5Ghz. What a waste of money. TP link should come up with a solution rather than expecting buyers to figure out with ISP's.

@ShashankB I dont exactly remember the solution. But i fiddled with the wifi names in the manual setup. I did not use the 
Quick start" option. Try adding the network manually and rename it (dont use the parent wifi name). Looks like the TP link extender gets confused with the other 5GH band in neighbourhood. Just a lame solution.... try doing it with other network is off....late nights or early morning. 

@ShashankB 

Try doing this. Go to you host router settings page (in case of Jio fibre login to  https://192.168.29.1 and login. Default user name is "admin" and password is "Jiocentrum")

After logging in, click the search icon on top right and type 'basic'. You'll see basic configuration for 2.4GHz and 5GHz, you can change the channel there.

Select 5GHz band and change the CHANNEL to 44 and width to 80MHZ.

This should do the trick. Or best, try calling TPLINK helpdesk.