Many seniors feel comfortable writing text messages, tweeting and surfing the Internet. But for those who don’t, taking the time to learn a new skill is often daunting, Kamber said. Older Adults Technology Services has taught 48,000 people how to get started online since the pandemic began and operates a technical support hotline. When vaccine registrations began, staff asked thousands of questions over the phone about booking appointments.

Regional Aging Agencies, part of a federally funded and overseen national aging network overseen by the Administration for Community Living, also help. Local chapters have called seniors and helped them register for vaccine appointments by phone or in person, said Sandy Markwood, executive director of regional agencies, which include more than 600 regional nonprofit centers run by state governments.

In Akron, Ohio, Lee Freund, 78, said every hospital, pharmacy, and grocery store she called looking for a vaccine directed her to a number of confusing websites. Ms. Freund could accidentally sign up for the delivery of groceries but was out of luck to argue a shot. There were tears in her eyes.

“When you’re alone, it’s frustrating, overwhelming, and very emotional,” said Ms. Freund, whose husband died last year. She said she didn’t call her children for help because she didn’t want to be a burden. “It almost made me think, ‘I don’t think it’s worth it.'”

Ms. Freund eventually found help at the nearby Aging Agency, where a woman made an appointment for her.

By the end of last week, only 12.3 million Americans age 75 and older, or 28 percent, had received at least one dose of coronavirus vaccine, according to the Centers for Disease Control and Prevention. Senator Tina Smith, a Democrat of Minnesota, who reintroduced a bill from last year to provide money to bring older Americans online, said the government failed to escape an avoidable crisis by acting high-level agencies not funded earlier.

Aging network organizations “have been overwhelmed by the needs and demands they have and are struggling to cope with the pandemic themselves,” Ms. Smith said in an interview. “We have too few resources and we are seeing the effects of them.”