I keep receiving robocalls where the callers identified themselves as Apple Fast Support. They claim there is something wrong with my cloud service, but I don't even use that. I have blocked all the numbers so far, but they keep using new ones. This is getting very annoying. The numbers all start with 1-989-275 and followed by various numbers.
I know scammers employ caller-ID spoofing techniques so as to impersonate the real telephone number of the service(FastSupport) they claim to be representing. Most commonly as far as this particular threat is concerned that will be Apple support, although I have been told by those on the receiving end of such calls that AppleCare and Apple customer service have also been used in an attempt to gain the trust of the victim.
But, I know Apple will never ask them for their Apple ID password, iCloud credentials or verification codes in order to provide you with support.