Well, being almost ignored when trying to trade for some converted pets is kinda normal imo. Most likely because not many people own the pet you want. And even if they do, they'll still ignore you if they think you don't have the kind of offers they want.
Have you tried searching the pound? Some jelly pets might get stuck in the pound. I can try to find one for you if you want to. Just pm me the species and I'll see if there are any.