Deceiving and dishonest company

I bought a KSTAR UPS. After 9 months the UPS did not perform per specification anymore and KSTAR/COREX now refuses to honor their 12 month warranty commitment on the main component (battery) of the UPS. I sent numerous communications why this is the case, but no answer obtained. Now they charging me to replace the batteries. I am truly disappointed in their poor service. So be careful for false adverti*****t of their warranty. This is an unreliable company.