Sat. 6/9/18 began downloading updates to Apple Computer when flash message on screen from Apple said to call phone number immediately. Called number (1-844-210-7888) man answers call as Apple computer technician Jason speaking. Assigned Apple Case ID #RTD 123856352412 and "discovered" security issues on computer which he could fix & install 3 yr. security warranty on computer for $400. He instructed setting up Apple On-Line Store Pay Wallet and began work. After some time, he said work to finish up would resume on Monday 6/11/18. Take computer Monday to Apple store where Tech says I’ve been scammed & technicians-installers were not Apple approved, i.e. frauds. They restored computer to factory settings.