The seller was either misinformed or lied. As the others have said, this is a pretty standard frogspawn coral. Given the price of Frogspawn vs. Hammers, I hope you didn't pay too much. These frags go for anywhere from $10-30 per head around me whereas most hammers are a good deal more expensive. The color looks pretty normal to me. When they are fully extended like yours are in the picture (which is a good thing), the color tends to be a little more muted and the tentacles can almost be sort of transparent.
Another thing to note is that lighting GREATLY impacts how colors show up on coral. Unless you have the same light set to the same settings as the seller you're buying from, it's most likely that your coral is going to look different in your tank than it did in theirs. It's pretty common for sellers to turn up the blues and use camera filters to get their corals glowing in pictures. But even if you saw it in person in their tank, the lighting was likely different. Keep that in mind going forward.