Proton Solar Distributors

I recently ordered and paid for an inverter at Proton. I actually received an inverter after two weeks, after complaining on Hellopeter ,but when the parcel arrived, it was obvious that it was not new. The barcode on the box did not match the one on the inverter and it was laying loose, only wrapped in bubble plastic. It charges the battery at 29,3Volts instead of 27,6V. How long will the battery last if charged like that? I'm very unhappy the way this company operates. If you reply to their mail, it does not get delivered. If this is not *****, I don't know what ***** is.