Amazon
I've had success with returning a product close to a year old. As long as u come up with a decent story you can usually get them to make a "one time exception" for the return. Their reps are usually kind and flexible and after telling them nicely a few times you don't really like there first and second offer,(ie partial refund etc.) they will usually give you what you want.
In 2 such cases they charged me a restocking fee, but I recontacted them and said I was promised a full refund, which they quickly fixed.
In general with contacting amazon for a favorable outcome I find email to be the best, then comes phone and worst is chat.