By Dave Carlin

NEW YORK (CBSNewYork) — Even though more sites for COVID vaccines are opening across New York City, it’s still challenging to get a shot.

New Yorkers are raising concerns about confusing websites and vanishing appointments.

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The Brooklyn Army Terminal mega vaccination site was locked up tight Saturday, even though it’s supposed to be open 24/7.

COVID VACCINE

Imagine the surprise of public school teacher Caitlin Palumbo when she showed up.

“I had an appointment today,” she told CBS2’s Dave Carlin.

Palumbo spoke to a guard at the site, who told her the site was closed and everyone’s appointments were rescheduled.

“They said that they’ve been rescheduled but I have not been notified,” Palumbo said. “It’s extremely frustrating, the lack of information and transparency.”

CORONAVIRUS PANDEMIC

“We thought we were all set. We got confirmation,” said Mike Morley, of Carmel in Putnam County.

Morley learned four appointments in a local hospital — for him, his wife, who is a teacher of children with special needs, and two relatives in their 80s — disappeared.

So he’s forced to start over.

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“We have spent day and night since Wednesday trying to get an appointment,” Morley said. “All we want is to be able to make an appointment.”

Vaccinations began at the Polo Grounds Senior Center in Washington Heights on Saturday morning.

Sixty-five-year-old Juan Rivera lives in Polo Grounds Towers, run by NYCHA, and lined up early for his.

“I’m very happy. We’re going in the right direction,” he said.

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Martha Cheathem was the first in her family to get the shot at one of three centers in NYCHA complexes that opened this weekend.

“I’m glad it went smoothly,” she said.

As New Yorkers flock to newly opened sites, it’s become clear demand is already outpacing supply.

Earlier this week Mount Sinai said vaccination appointments had to be canceled due to low supply.

Mayor Bill de Blasio made a dire prediction Friday that doses of vaccine could run out by next week, causing the scramble to get one to intensify even more.

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Dave Carlin