An upstate New York lawmaker is calling for an investigation into a well-known veterans advocate — accusing her of lying when she claimed ex-military were getting booted from hotels to make way for the flood of migrants up north.

State Assemblyman Brian Maher, who’s worked with Sharon Toney-Finch and her Yerik Israel Toney Foundation for three years, said he’s “devastated and disheartened” after her story allegedly began to unravel this week.

Toney-Finch, an Army veteran herself, claimed on Friday that 20 ex-military were told earlier this month they could no longer stay at three hotels in Orange County because asylum seekers were being bussed there from the Big Apple.

“Thankfully, my team and I were able to scramble and find new temporary housing for these veterans,” she wrote on social media about the alleged plight.

“However, this extra trauma has been difficult as we work to gain trust and continue to support these veterans as they reintegrate back into society. Whether you agree or disagree with migrants being housed in the Hudson Valley, I think all of us can agree that this issue should not negatively impact our homeless veterans who have sacrificed so much for our country.”

But on Thursday, Maher said Toney-Finch admitted to him that she’d lied when he pressed her to provide bank records proving her nonprofit paid for the hotel housing for veterans.

“I asked her to give her permission to the bank to release the information. She denied authorization,” Maher told The Post. “After two minutes, I called her back and explained how I was feeling about not being able to see that information and then I asked her if that was something she made up and that’s when she really had a hard time getting the words out — this is someone who I worked with over the last 3 years — but she did reveal to me that this is not something that took place.

“Shortly after that when I asked her why she would make something like that up. She said, ‘I had to help the veterans.’” 

The bizarre twist in New York’s mounting migrant debacle came to light when management at Crossroads Hotel in Newburgh denied that veterans associated with YIT ever stayed there, as first reported Wednesday by Mid Hudson News.

Maher — who told The Post he’d spoken in person to two YIT veterans allegedly affected by the move on Friday — provided the local outlet and The Post with a purported receipt from Toney-Finch appearing to show she shelled out $37,800 to Crossroads Hotel in Newburgh on April 12.

A Crossroads manager told The Post Thursday that staff searched their system after the reports first emerged they had supposedly booted the veterans, but found no reference of the YIT Foundation nor Toney-Finch’s name.

“I scoured the system, I mean we went back and there were no veteran organizations,” said the manager, who didn’t want to be identified.

“There were no, absolutely no, veterans that were staying here that were asked to leave because of, you know, the migrants that were coming to stay here. Nobody was evicted. That’s for sure.”

Toney-Finch insisted that 15 vets were punted from the Crossroads, while five other veterans were displaced from the Super 8 and Hampton Inn & Suites in Middletown.  

None of the three hotels responded to The Post’s repeated requests for comments about the displaced veterans Friday. The Hampton Inn and Super 8 have since denied Toney-Finch’s claims.

Maher — a Republican representing a part of Orange County and who over the weekend referred to Toney-Finch and her team as “some of the hardest working and dedicated community advocates I know” — said he had no reason to doubt the Crossroads receipt initially.

Maher said Toney-Finch even took him to meet the pair of veterans on May 12 after she said she moved them to the Wingate by Wyndham in Fishkill — though he’s unclear now who they were.

The YIT CEO was a no-show Thursday when Maher asked her to meet in person.

“I am devastated and disheartened upon a conversation with Sharon Toney-Finch at approximately 3:15 p.m. today, where I learned that the information regarding the YIT Foundation about homeless veterans being displaced is false,” Maher later said in a statement.

“Their gross misrepresentation of the facts surrounding our homeless veterans is appalling.”

Toney-Finch, who did two tours in Iraq, also repeatedly refused to let The Post speak to any of the affected veterans.

The Post went to the Wingate hotel earlier this week, but was unable to track down any of the allegedly displaced veterans.

In a since-deleted Facebook post, Toney-Finch lauded Wingate for helping.

“Our Homeless Veterans will always come first!!!!! Thank you Wingate Fishkill Hotel for taking in 20 of misplaced Veterans of YIT Foundation due to the misplace they had to deal with cause of the crisis that is going on across Hudson Valley,” she wrote. “Looking forward to be there … to thank you all in person.”

Reps. Pat Ryan (D-Gardiner) and Marc Molinaro (R-Red Hook) both put out statements in support of Toney-Finch’s supposed efforts to rehouse the displaced veterans.

On Thursday, when asked about Maher’s allegations, she pointed the finger back at Maher and said she has “nothing to hide.”

“So there were veterans but … I honestly think that he made it bigger than what it was,” she said. “What I’m going to just say is, we’re gonna continue our mission on helping veterans and families, as we’ve been doing, that’s just all I’m gonna say.”

She also insisted that she’d paid for the veterans to stay at hotels but refused to provide bank statements. She claimed she brought the 20 veterans to the Orange County New York Veterans Center Wednesday in New Windsor.

In the wake of the ordeal, Maher said he’s severed ties with YIT and is now calling on the New York State Attorney General’s office and the Orange County District Attorney to probe Toney-Finch’s foundation.   

“I am calling for an immediate investigation by the New York State Attorney General’s office and the Orange County District Attorney into the YIT Foundation based on the new information that came to light today,” he said. 

“The YIT Foundation purports to protect and support veterans, but the dishonest claims and fabrication of the facts by YIT does enormous harm to our homeless veterans by creating mistrust.”

David Hoovler, the Orange County DA, said, “Right now there’s no allegations of missing money that we are aware of, or anyone making a complaint of misappropriation of missing money.

“The only thing we have been made aware of is that the head of the YIT Foundation may have embellished a story. The matter is being referred to the AGs charity bureau and if someone comes forth saying there is missing money or missing funds, then obviously we will investigate.”

He also mentioned that the foundation is “heavily involved” in the local community including other veterans organizations and chamber of commerce but “No one has come forward about missing money or misappropriation.”

The AG’s office didn’t immediately respond to The Post.