Not honest about product and service

I am really worried about the product and the service I have received. Firstly, the box was opened when it was delivered and no manual inside, just watchpower CD and a sticker saying it's a 7.2kwh battery. No other specifications on the product. Secondly, the battery not connecting to the inverter. Thirdly, the delays and empty promises in delivery and replacement of battery.

Don't question about the authenticity of the product, they stop communicating.

They also use different company names. Something not adding up.