Some random person calling to tell you you're due free money and you thought it was on the level?! You say you've been scammed before so I would think that would make you more cautious about this sort of thing. Lucky you didn't have the money to lose because you definitely would have lost it! Grants are applied for, not just given away for being a good citizen or paying your taxes on time or whatever other lie they come up with.
I was called multiple times throughout the day and I finally was around my phone when they called, it was a lady that had an accent saying something about $9,000 and knew my name. I asked if she could not call me again and said "no I cannot do that." and hung up, I have already seen this thread prior to talking on the phone, definitely a scam.
I answered it and it was a woman but a lot of scratchy noise I got bit of peaces of the convo something about she calling from the united states I'm like umm duh and something about money told her not interested and hung up sounds like a scam to me