if theyre a hybrid they cant breed i believe? I could be wrong
If you got them from someone and they were hacked then they won't breed. Hacked flowers can't breed at all, they just produce nothing or normal color flowers.
ah, alright. they were probably hacked then if they aren't producing anything.
The ultimate solution? Try them breeding yourself or buy some from a trustworthy, actual hybreeder.
If you intend to breed purple tulips from scratch, you'll first need to breed orange tulips from red and yellow. Once you have bred 2 orange tulips, you can continue to spawn more orange or begin spawning purple.