I have the same issue as user @PatriceLep as reported at https://community.tp-link.com/en/home/forum/topic/666492

I am therefore interested in knowing how this user issue could be solved.

I am using a Deco X50 5G in France, with the same "Free" sim card as PatriceLep. Free is a French telco.

Deco can perfectly receive SMS but cannot send. This is a new issue as I have been able to receive 5G backhaul activation notification in the past.

5G is working fine with the sim card.

SMS reception is swift.

Upon sending a SMS, I have a "failed" error message.

I can perfectly send sms on mobile phones with the sim card (IOS or Android).

Issue can be reproduced with either using international phone number with :

+ sign and country code,  and phone number

area code + phone number

country code and area code and phone number

00 and country code and phone number

...

Thanks for your support.

Sonysan