HELP!...Leaky Bathtub faucet even after I replaced both cartridges

Hello. I am hoping someone that can help me. I live in a condo that was built in the 1980's. I have a slow drip coming from my shower / bathtub faucet. I cannot find the exact name brand of the faucet, as it has no markings. It is a two handled and the diverter is in the faucet itself.

I took apart both the hot and cold faucets and inspected the cartridge and found no apparent damage or wear. I couldn't find the replacement part at my local hardware store. Though, after about a week Google image searching I found the manufacture of the cartridge. It's made by a company called Phoenix Faucets, what they call "Plastic Cartridge for Phoenix, Nibco and Streamway 2 Handle Kitchen or Lav Faucets and Exposed Tub & Shower Faucets, Fits Hot and Cold on Knob Handle Faucets or Hot Side Only for Lever Handle Faucets" with a part number was p22. I ordered two of them and replaced them both, however the leak still remains the same. I'm not sure what else there is to replace other than installing a whole new faucet, which I would like to avoid.

Any help would be greatly appreciated!

Library Guy

WE can't answer the question because we do not know it that is really the correct part, or if you installed it correctly, or if there is a removable seat that has to be replaced.