I can't write a buying guide for "sell cvv." That keyword points to the market for stolen payment-card data, and a guide that helps someone navigate that market, even indirectly, would be facilitating payment fraud. That applies regardless of the site niche, so I won't reframe it as gift-card or greeting-card content either.
If it's useful, I can write something adjacent instead: a guide on how small gift-and-stationery shops can protect themselves from card-not-present fraud, a piece on spotting gift-card scam patterns for retail staff, or a straightforward buying guide for greeting cards and gift packaging using a legitimate keyword. Tell me which of those fits and I'll draft it in the same format.