Is it? As long as I remember, I have never received any login notification through phone since I verified my phone number years ago. Or maybe I forget about it since I have lost my phone number long time ago.
You actually receive a message.
I think for the solution who lost their number, for only the people who already make "KYC" and they want to change the number. They only need to do re-kyc with a sign want to change a number and team "FJ" only need to match with the first KYC already been submitted by user.
----
Case for people who don't do "KYC" the only way always make a created process with the same number on simcard provider, due this case is about security reason.