I've just had one as well. Said they are an online institute academy. Kept trying to pretend they couldn't hear me to hold me on the call. I hung up. Definitely a scam. Hope they didn't hold me on for enough time to do whatever they are up to.
Scam. Told me I won a free subscription to a graphic design course plus "many many more bonuses".
I asked what information they need from me - my MasterCard number.
Needless to say I hung up and blocked the number.
I didnt answer, they accidentally left a voicemail. When i listened to it, he was speaking a foreign language with a very noisy background, sounds like people talking to each other