Overcharged by Spectrum.Stream Porto Alegre for service

I want to report a serious concern with Spectrum.Stream Porto Alegre's unit that I purchased on June 28, 1991 from your South Elbertberg, New Jersey store. The product has had repeated billing errors despite being advertised as high quality. I've contacted customer service three times and spoken to Kara V., but my issue remains unresolved.

I want to report a serious concern with Spectrum.Stream Porto Alegre's unit that I purchased on June 28, 1991 from your South Elbertberg, New Jersey store. The product has had repeated billing errors despite being advertised as high quality. I've contacted customer service three times and spoken to Kara V., but my issue remains unresolved.