incoming SMS to purchased number - fails from a certain sender

i purchased a phone number for a SIM card to receive incoming SMS messages.
i can receive messages sent from the dashboard, and from other carriers’ network, so everything appears to be set up correctly.
yet i consistently fail to receive registration SMS messages for a certain website. there is no trace of them in the activity log.
is there maybe a filtering set up somewhere?

There’s no filtering on our end. Have you reached out to the website sending the SMS to see if it might be on their unsubscribe list or anything?

thanks for the quick confirmation on no filtering!

i did not check with them yet, but i purchased 3 different numbers from 2 countries of interest, none of them worked yet. i might try a few more numbers, but it would probably be a too low success rate for deployment in any case, so we might need to find another solution.

(are you recycling numbers?)

We get the numbers from another telecom service that maintains a huge pool of numbers to sell. It’s very possible that numbers have been used before by other customers since when they are released they go back into their pool.
Very strange that none of them work though. Seems like it’s an issue on the other side if that’s the case.