Disgusted at Servicing Department

I've been a loyal customer of Teljoy's for the last 48 months (if not more), where I've rented a DSTV HD PVR decoder on the rent to own basis. I did this merely because I didn't have the cash at the time to purchase one at the time. So after 36 months, (and about R12000 later) I finally owned the decoder. That is after it was replaced 4 times. Currently have the 4th one from Teljoy. I opted to take the service offer for a minimal amount per month just in case I had to replace another decoder. Teljoy diligently took their money every month. We just moved to a new place, and seeing that I now own my decoder I got an installer of my choice. We had TV for one day and now the decoder keep on rebooting itself and is now stuck on the booting phase. Phoned Teljoy to replace and they declined to assist as I didn't use their installers. Said I must call my installer as it's a faulty installation. IT IS NOT A FAULTY INSTALLATION, THE DECODER IS FAULTY. IT DOESN'T BOOT UP. The values on you website are absolute lies. Seeing that my money for the servicing is not good enough I demand a refund for all the months I paid for the servicing, but not gonna get. The money or the device?