SPRINGFIELD, Ill. (NEXSTAR) — Springfield Clinic sent a letter to the Illinois Department of Insurance, questioning the scope of the department’s investigation into Blue Cross Blue Shield of Illinois.

The department’s investigation found the network had an “adequate” patient to provider ratio.

Springfield Clinic did its own analysis of the directory, and told IDOI they found nearly 100 Springfield Clinic providers in the directory that should not be there.

“It has been a year and a half,” Zach Kerker, Vice President of Brand Experience and Advocacy at Springfield Clinic, said. “And still you have 100 providers listed. That’s either intentional or just incompetence. But either way, it’s our patients who are suffering as a result of it.”

In response to the letter from the clinic, the department doubled down on its investigation.

“The department recently concluded a market conduct exam with findings related to updating provider directories and is committed to ensuring that blue cross blue shield of Illinois comes into compliance with the resulting director’s order,” a spokesperson for IDOI said in a statement.

Blue Cross Blue Shield of Illinois defended its directories, as well.

“We strive to provide our members with useful information about the availability of network providers through a directory that is up-to-date, accurate, and complete in compliance with the law,” a spokesperson for Blue Cross Blue Shield of Illinois said. “It is typical for many providers to have affiliations with more than one health system, hospital, or facility.”

Since the clinic and health insurance company parted ways nearly 18 months ago , the clinic says it’s still helping patients find new in-network doctors. They want to make sure the state is actually holding companies accountable.

“What legislation must come into place that provides true enforcement and true accountability for insurers who are potentially miss intentionally misleading patients?” Kerker said. “I think that that’s a question that we’re asking ourselves. And we’re asking it because someone has to ask it on behalf of the patients.