One thing I would like to know from the seller.

Did you have any proof to show that you are selling AP phone to buyer? If you have the proof, then you can clear your name there as buyer might be mis-read it.
After reading all 5 pages of comment in here, I didn't see any proof where you stated you are selling AP set, even though many people have asked you.

On the Apis's part where he's bias or seller, I can concur that he's the seller before promoted to Mod. From what my observation, Admin will only remove your dispute tag once they gotten confirmation from seller or the victim. Admin need prove to show that you have already resolve the issue.

Do you still have buyer's hp number? Perhap calling him to solve the issue faster than PM/email to him. Once sorted it out, then can give conclusion/answer to all of us.