How do you get Grandma to stop buying stuff from commercials?

How do you get Grandma to stop buying stuff from commercials?

"My Grandma lives on her own and recently she’s been buying a lot of stuff off of TV. She'll see a commercial, buy the item, then forgets she bought it and buy it again.
I don’t want to take away her phone because we need to communicate with her, and I don’t want to cancel her cable because she loves watching the news and her shows."