Unreliable Solar Equipment supplier (Tech Sun Solar)

I have purchase Solar Equipment through Techsun Solar in Midrand on 2 different occasions were by i specifically ask if there is any physical appearance differences as to the first batch ,and there answer was nothing will be different. Only to find out after paying and receiving the goods that there was some differences on the LED of the batteries supp****. On taking the on they ask me to return the battery as for them to change the LED to match the first batch.I went through a lot of cost and time to do so ,only to find nothing were dine at all. Now they blame it on China that has made some Changes to the production line. and that Techsun Solar can not assist in exchanging the battery.