Hello @Gaylin57, are you referring the the call made to the Taxi service from your other post? It's highly unlikely that someone used your number, many times when you get a SIM card things like directory look-up, Taxi, and emergency services are preprogrammed on the card, is it possible you accidentally hit one of those preprogrammed numbers?
Either way, you will need to speak to customer service directly as they are the only ones that have access to your account and can better assist you, see here for all the different methods to contact them.
