Thanks for nothin’, Mayor.

An East Village couple is furious that heedless contractors working on a condo building next door mistakenly chopped down their beloved, six-story-tall backyard Norway Maple — and they say Mayor de Blasio only added insult to injury with an empty promise to help.

Alexander Poma, 50, and Leslie Steven, 60, of East Seventh Street, say they got a bureaucratic runaround from the NYPD, Parks Department and Department of Buildings before dialing into the mayor’s call-in show
on WNYC Friday to complain about the blunder by a subcontractor of L&M Development, which is building a high-rise next door.

On the show, the mayor personally promised to help them.

“I did get a call from the Mayor’s Office from someone who didn’t understand the problem,” Steven said. “She said, ‘I’m glad your electricity is back up.’ ” Replacing the tree would cost $150,000, Steven said an appraiser told her.