@Sunshine Hey I'm having the same issue with Jio sim.

Router Model - MR6400 V5, 

Firmware Version - 1.1.0 0.9.1 v0001.0 Build 200511 Rel.43036n,

Bought it a week ago and reset it once because SSID was different than mentioned on the box but resetting took care of that.

If someone has solution, please help.

@Sunshine 

Good day.

Sorry for the delay.

If you check on the basic page, Is there any message showing up here?

No. There are no messages.

By the way, what is your current firmware on the modem, the numbers after the build?

Firmware Version:1.7.0 0.9.1 v0001.0 Build 181214 Rel.49556n 

How long have you had the device and did it start since out of box？

I had this device from July 2020 and the issue started since out of box

Have you tried to factory reset the modem before?

Yes. I tried it. 

Thank you very much.

@Sunshine

I have updated my firmware version (New Firmware Version:1.10.0 0.9.1 v0001.0 Build 190521 Rel.38696n) as recommended, but still, cannot receive/send SMS. I look forward to your further help.

Thank you

Jince Shajan

Im having the same issues, cant receive and send sms since out of box tl-mr6400 v4 00000002, with cellular operator 3, in indonesia, and already try update firmware as recommended, but still cant receive and send sms

@jinceshajan These TP link people just know to lie their customers that they are working on it.I m having similar issue in my MR 100 n I hv already reported multiple times but till now I haven't received any satisfactory response from their side