Amazon Happy buy Defective tool sold by happybuy through Amazon required return Internet

I purchased a rebar bender for my business at 469.99 defective tool from the day we first used it Amazon failed to refund the purchase price and company happybuy refused to refund the purchase price. Amazon required we return it to the seller for refund after spending 96.or 97 dollars for shipping the broken defective product we have been given every excuse under the sun to not refund my money after promise to do so . We supplied tracking number for the tool and apply for the a-z refund and was never refunded anything story after story so end result we we're robbed for almost 600 dollars by Amazon and happybuy through them. They have no action from either one absolutely robbed