SAN FRANCISCO (KGO) -- An elderly San Francisco woman and her sons are accusing two Uber drivers of trying to force her to pay them in cash. For many seniors, using an app can be foreign, and that can leave them vulnerable. She said two drivers took advantage of that.Betty Forsyth lives in San Francisco. The 88-year-old has been fairly independent until her doctors ordered her to stop driving due to health issues. Now her car sits in her garage and when she needs to go somewhere, she takes Uber."My son in Seattle set everything up for me. And he would make all the arrangements," said Betty.In fact, Betty doesn't even carry a cell phone."What's an app," an ABC7 producer asked."I don't know," said Betty.Whenever Betty needs to go somewhere, her son orders her an Uber and follows her progress on the app. "I could see her driver initiate the ride and deliver her to the appointed area," said her son Thomas Forsyth.Her son paid through the app, but Betty says after her first ride, the driver asked her for 20 dollars and she gave it to him, along with a five dollar tip."She was confused," he said."The first ride I had with them. I didn't know," explained Betty. "I thought it was like any other cab company."Things went smoother the next few times until one Saturday, she says another driver demanded money from her."Then he said to me, sign your name. Sign your name. And I said what? And he said sign your name and I said what for?" said Betty.Betty promptly got out of the Uber and called her son John who also lives in San Francisco."I think that these guys are looking to prey upon our most vulnerable citizens, elderly people," John said.We reached out to Uber and the rideshare company told us: "Uber is designed to be a cashless experience. Violations of Uber's Community Guidelines can result in drivers losing access to the app."The driver involved in the second incident has been removed from the app. The family says they have received a refund for the first trip.Uber advises any passenger asked for cash to end the trip and report the incident to Uber immediately.The two incidents have left a sour taste in Betty's mouth."I was ticked that somebody took me," she said.We checked around and found anecdotal evidence this has happened to others, but police tell us statistics for this type of incident are not kept.