Kevin McCarthy of Thousand Oaks, California, was surprised last spring, when he learned his family doctor of 14 years could not accept the Blue Shield insurance he'd purchased under Obamacare.

He said he was "outraged" because when he was shopping for his policy, Blue Shield confirmed his doctor was covered.

Kevin McCarthy CBS News

"We were duped," McCarthy said. "Hoodwinked is another good term."

Here's what happened. Insurance companies -- to save money -- are quietly selling what are called "narrow networks." They sharply restrict the number of doctors and hospitals people can see. In some cases, people may be limited to 30 percent or less of the doctors and hospitals nearby.

Jerry Flanagan, lead attorney for the Consumer Watchdog group in California, says hundreds of thousands of people lost their doctors when insurers sold narrow networks without notice.

"Consumers here were told that networks are going to be the same as they were before Obamacare ... and those are flat out lies," Flanagan said.

The upside to narrow networks is the low cost, because the doctors in these networks have agreed to discounts. The savings to consumers averages 13 to 17 percent, according to the respected McKinsey consulting firm.

Blue Shield of California chose not to appear on camera but denies it intentionally misled its customers. The company blames the problem of lost doctors on the frantic transition to Obamacare but promises this year it will "address network confusion by communicating more clearly with members."

There are two important things consumers should remember. Narrow networks are the new reality in Obamacare. And anyone who wants to be sure their doctor is in network needs to call the company to confirm and they need to keep records.