By Dana Kozlov

CHICAGO (CBS) – Critics of short term insurance plans say they can be a long term disaster, saying they’re often misleading, leaving people without the coverage they thought they had.

29-year-old Sam Bloechl was diagnosed with Stage 4, non-Hodgkins lymphoma in January 2017.

Bloechl thought his Golden Rule United Healthcare Insurance Policy had him covered.

Instead, his claims were denied and he was left almost a million dollars in debt.

“It’s becoming a bigger and bigger issue and still something hanging over my head,” said Bloechl.

“Short term plans are like the wild west of insurance in Illinois, they can discriminate against people with pre-existing conditions,” said Kathy Waligora, MSW of EverThrive Illinois.

Many advocacy groups and lawmakers, including state Senator Heather Steans, are fighting to regulate them in advance of a pending federal rule allowing for their expansion.

“I think it’s really an end run around the ACA. So if we do not do something to regulate those plans here, people may get stuck in a situation where they don’t have real health care coverage and they don’t even know that,” said Sen. Heather Stearns.

Steans is sponsoring a bill that would limit short term plans to 90 days, require they cover essential health services, and market themselves clearly.

“Actually require every material to have something that says ‘Warning, this offers limited benefits and may leave you with high medical bills,’” said Waligora.

Bloechl, who’s since testified before a congressional panel about the pitfalls of short term plans, thinks it would help.

“I have no doubt that I was wronged by an insurance company,” said Bloechl.

They say a pending federal rule, allowing for the expansion of short term plans, would leave more people vulnerable.

Critics say studies show that, over time, term plans will force full coverage premiums to rise.

In February, United Healthcare started short term insurance can be an option for those who temporarily lose coverage, but isn’t meant to replace full coverage plans.