Customers are complaining that Amazon’s ads use a deceptive design that tricks them into buying sponsored products instead of items from the baby registries of their friends and family members, reports The Wall Street Journal. Many people noted that they had unwittingly purchased gifts from these ads and their friends and family received unwanted items.

Inside the gift registries, Amazon appears to be including other new baby products like a Playtex Diaper Genie and Kimberly-Clark’s Huggies Snug & Dry diapers as sponsored ads. The ads are placed next to actual products requested by people, making them look as if they are a part of the wishlist, except for a small sponsored tag on top. The WSJ notes that these tricky ad designs have existed for at least over a year, but it’s just starting to get noticed. About 60 percent of sponsored ads are included in registries, even though parents do have the option to remove those sponsored items. Amazon did not clarify whether these ads were intentionally left in. These sponsored ads cost advertisers $500,000 per spot.

The Federal Trade Commission states that ads must stand out and be distinguishable from non-ads to consumers, but Amazon’s sponsored tag is small and gray and can be easily overlooked. Amazon told the WSJ: “We’re constantly experimenting with new ways to improve the shopping experiences for customers.” We’ve reached out for additional comment and will update if we hear back.