The plot twist: The one who changed your gmail password is the seller of those accounts.
I'm bit confused why you had to buy gmail account if you could make it yourself. Well mate, I think there is no solution for that.
yes jayce no solution for recover his account.I was trying to recover but he had nothing to recover like he dont know recovery mail,he dont know when account was created and password also not old one.I think who sold him account he changed everything.I am not sure why people buy account for personal use. its not very hard to open an account.