How do you unlink ITunes Store accounts

[iMore Question]

My son used my Ipod and signed into the ITunes store to listen to his music. He signed out after he was done. The problem is now after signing myself back into the account, it keeps asking me for his password. I have tried resetting the Ipod to factory resets, etc. and nothing seems to work. How do I unlink him from this?

 

[Just_Me_D]

Are you certain you signed in with your Apple ID and passcode? Did he download music onto your device?