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Without knowing the details, it’s hard to say. Yes this could be a spam tactic but various industries have laws saying they have to contact their users/clients/customers if they make a change- e.g. your bank has to notify you of new charges.
Not a defense of someone using this to scam, but an explanation of why that language might be used if legitimate.
It was for them having a sale and giving me an extra $50 off if I use my card.