Roku has nothing to do with any ads on that channel. You'd need to contact the channel provider, which for HGTV is Discovery.com. I looked at their corporate web site, but I don't see any specific link to a support page.
No need to return the TV, as a) Roku didn't build the TV, some other company did, and b) that company had nothing to do with those ads either. Getting upset at Roku is misdirected anger.
Dan
Roku Community Streaming Expert
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