This article applied to: 
All TP-Link 4G Routers

Problem Description:
Some Indian users reported that they cannot send or receive any SMS with Jio SIM on the LTE routers while it is perfectly working with other SIM carriers, like Airtel SIM. And if we check the system log, the following log would appear:

Solution:
After further troubleshooting, we have found that Jio requires to enable VoLTE in order to use the SMS function. The SMS doesn’t work even on mobile phones with Jio SIM if you disable VoLTE on the phone, so when users have Archer MR600 or other non-VoLTE compatible models with Jio SIM, the internet service is still working but SMS would fail to work properly.

If anyone plans to purchase a TP-Link 4G router to use with Jio SIM and require to use SMS function, TL-MR6500v would be a better option because it supports VoLTE. And you could enable VoLTE on the MR6500v web interface:

However, if you have bought a non-VoLTE compatible router and would like to use Jio SIM, we are afraid the SMS will not work, and for comparison, you could also test the same SIM on your mobile phone with VoLTE disabled. 

Note:

1. For other SMS issues not mentioned here, please refer to the suggestion on this link:

[Solution] Cannot read SMS messages on TP-Link 4G Routers

2. If your SIM carrier is not Jio, but you happen to have the same errors on the system log, please also test the same SIM card on your mobile phone with VoLTE disabled. After testing, if your SIM carrier also requires VoLTE for SMS service, please comment below with your location and the name of SIM carrier. We will have further confirmation with the local support team.