Thank you for the fast reply, but apparently, that was not the issue since we have ample of credits purchased in the account.
Regardless, it was adding the ’00’ in front of the phone code, thus, it was not sending the code to the “correct” mobile number.
I would also like to ask if it is possible to increase the expiration time of the code. As far as I have understood, the received code is valid for one minute, right? Is there a way to increase it to 10 minutes, for example?