THAT MEANS IT’S WORKING: ObamaCare problems deepen as insurers scramble to stem losses.

One by one, the nation’s top insurers – Humana, UnitedHealth Group, Blue Cross and Anthem – have shifted their tone on the law.

Once optimistic, each has reported struggles with plans sold on the exchanges. Many say they weren’t ready for the influx of customers that have generated more claims than predicted.

As a result, companies are scrambling to find ways to cut their losses and stop the fiscal bleeding. A few say they’ll be forced to pass on costs to customers.

Already, rates on the exchanges are skyrocketing. From 2013 to 2016, almost every state has seen an increase in monthly premiums. In Michigan they are expected to jump 17.3 percent this year. In Virginia, the average premium increase could hit 37.1 percent, Bryan Rotella, attorney and founder of the Rotella Legal Group, warns.

“In fact, two of three federal programs to manage this exact risk are due to expire in 2017,” Rotella wrote in an opinion piece for The Hill. “Without these programs to fall back on, many insurance companies likely will need to jack up their premiums even higher or bail out of the exchanges all together.”

Blue Cross reported losing hundreds of millions of dollars on its exchange plans across the country. In Tennessee, it took a $300 million hit; in North Carolina, $280 million and in Arizona, $135 million.

In California, the company is expected to raise rates 19.9 percent – more than triple the average annual increase.

Others like Humana are threatening to quit altogether.

Something that can’t go on forever, won’t.