Same thing happened to me today.  Recorded message said an amount will be debited from my card and call them.  
i called the scammer and he said “I purchased a gift card last night”.  
and if I want to cancel the order I need  to download an application called TEAMVIEWER from play store and that’s when it clicked that they were trying to gain access to my phone.   I hang up and told them that I’ll call my bank and report a fraudulent transaction.