The way this scam works is by claiming you have won a "free prize", but that you must pay a small fee in order to claim it.
They claim you only need to pay a few dollars, but also that the "free prize" is in lieu of accepting a fee based offer or service.
If you give them your card or account info, you are auto-signed up for one or more fee based services that are extremely difficult to opt-out of, have no real value, and have a weekly or monthly reoccurring charge. If you do manage to contact someone at those services to have the service stopped and fees reversed, you will find out that most will not credit back the fees or stop debiting your card or account, requiring you to close the accounts.
Further, you find out that in order to receive your "free prize", you will need to use these services for some time, resulting in accrued fees that greatly exceed the value of the "free prize".
If for some strange reason, you still find all of this acceptable and proceed with paying all of the fees, you then find out that the original "company" aka scammer that offered the "free prize" is long gone. You get no "free prize" and have paid many times more than what you could have just purchased the "free prize" on your own.
Rang once and hung up. I have a no ring ringtone and now 11 contacts named stupid 1, 2, . . . 11 with five numbers each. It still shows the call but at least I don't hear it.