A few days ago I received a Walmart card good for up to $400. Got it registered, but don't think I will use it as I don't like making monthly payments. Then I received a letter from PayPal that said I had asked for $188.11 credit to shop at Walmart. Fortunately, they refused me. I called one credit check company who said they would notify the other two and my account now has an "Alert" on it, and none will take any action of sending a credit report until they call me.
I called Walmart and cancelled the card.
I do my shopping on line and wonder if I should also notify anyone else I shop with, like Chewys for my cat food; Montgomery Ward; Penneys; Overstock. And I pay my bills with my credit card by calling their 800 numbers - telephone, Montgomery Ward, other bills.
Don't accept or follow up on any unsolicited "gifts" from people you don't know. That's the first thing. No one just gifts people out of the blue, for no apparent or fathomable reason, especially if they are fronting for a "business". The problem as I see it is you are naive to a fault, and suspicious always, particularly when you've been had. You don't have to invite it in, in the first place. Long way to say if it seems too good to be true, it usually is.