Citi Field finally opened as a COVID-19 vaccination site on Wednesday but demand far outstripped the meager supply — with dozens of desperate elderly locals showing up with no appointment, only to go home disappointed

“I’ve been waiting here for over two hours in the cold. I have been trying to get an appointment for four weeks, but can’t and nobody here is helping us,” said Maria Fernandez, 77, outside of the home turf of the Mets.

“There are so many reporters, photographers here, but there are no vaccines,” she said. “What are we supposed to do?”

The stadium officially opened for coronavirus vaccinations at 10 a.m. Wednesday following weeks of delays due to a shortage of the coveted shots. The site is supposed to serve borough residents as well as taxi drivers and restaurant workers.

But officials this week admitted that it would only have around 800 shots for the rest of the week. During a visit Wednesday, Mayor Bill de Blasio promised that would be upped to 4,000 doses a week by next week.

He also vowed that anyone who shows up without an appointment will be given help to make one for a future date.

“There’s no such thing as walk-up and get a vaccination anywhere,” Hizzoner said. “We do not want long lines. We do not want people congregating anywhere.”

However, following the press conference, Annabel Palma, the chief equity officer for the city’s COVID-19 Test and Trace Corps, was seen telling a group of about eight people hoping to get inoculated that future appointments could not be made for them at the moment.

“We can’t register you because there aren’t vaccines,” Palma told the group in Spanish. “We aren’t going to give you an appointment if we don’t know for sure.”

Longtime Queens resident Felix Hojas, 69, then interjected that “the mayor is a liar or you are betraying us again.”

“Nobody is betraying you. Nobody is betraying the community,” Palma said before leaving.

When asked about the matter by The Post at a later City Hall press briefing, de Blasio said, “This is a situation that needs to be addressed by us getting the [vaccine] supply that we deserve.”

Elderly residents said they’ve been trying to get appointments at home to no avail.

“They announced on TV that this was opening up for Queens and people would be able to get vaccines,” said Elva Marchena, 79, who arrived at the stadium with her sister and 82-year-old husband.

“I have cancer and had a knee replacement. I need a vaccine. I have been trying to get an appointment for weeks, but can’t.”

Many old timers reported being flummoxed by the city’s convoluted online sign-up system.

“We have to fight for a vaccine. I am 80 years old. I don’t know how to go online,” said Nelly Torres after being turned away. “Why can’t they just make an appointment for us here?”

Spanish-speaking locals also fumed about being unable to score appointments by phone.

“It’s not fair,” said Francia Gordilla, 74. “We’ve been calling and calling and going on the computer for weeks and weeks and we can’t get an appointment.”

De Blasio on Wednesday said that the city is working on improving the buggy online appointment system.

“We’ve added different languages for the appointment application. We’ve made it clear where there are doses, where there are not, so people don’t put too much time into pursuing a site where there’s no doses,” said de Blasio, adding, “We will have more to say on this soon.”

The city says roughly 200 appointments a day will be available for the first week at Citi Field, which is just a small fraction of the nearly 2,200 vaccine daily doses that the state-run Yankee Stadium in the Bronx is receiving.

Yankee Stadium opened as a mega-immunization hub on Friday.

Additional reporting by Nolan Hicks