I would advise starting a web chat with Smarty support urgently and asking if they can shed any light on it, and also asking them to cancel it. It may be that someone is attempting to do a SIM swap scam, i.e. trying to port your number to another SIM so that they can then receive things like 2FA (authentication) codes sent to your number. It might also be a good idea to change your Smarty account password.
