Cole's CEO Ashley Buchanan was fired this week because he had an undisclosed personal relationship with the consulting team, which reached a multi-million dollar direction with retailers, the company said in regulatory filings.

Buchanan has held the position since January.

A survey by an external law firm found Buchanan directed the company to enter “a supplier deal involving undisclosed conflict of interest” in violation of company policies, the department store said.

The company said Cole's board of directors terminated Buchanan and appointed Michael Bender, the board director, as interim CEO.

Cole said Buchanan's sack had nothing to do with the company's performance and had no other employees. Buchanan has previously held the same position since 2020 at craftsman retailer Michaels. He became CEO of Kohl in January.

Cole said in a regulatory filing with the SEC on Wednesday that the investigation found that Buchanan directed the company to “have personal relationships with very unusual conditions that Mr. Buchanan has established to operate in very unusual conditions that are beneficial to the supplier.”

The person, who spoke on condition of anonymity, is also part of the consulting team, which has reached a multi-million-dollar deal with Cole under Buchanan's guidance, the document said.

Regulatory documents say Buchanan did not disclose the relationship in accordance with company policies and he would have to receive all equity prizes and bonuses from Cole when he was employed. He also had to pay back the company with a $2.5 million signing bonus.

Cole did not disclose who the consulting agreement was with, but the Wall Street Journal first reported that Buchanan was fired, saying it was the Boston Consulting Group, with Buchanan's romantic partner Chandra Holt as a consultant. The magazine report quoted unnamed people familiar with the matter.

Buchanan and Holt did not immediately respond to requests to comment by phone and email.

"I was shocked to learn about the relationship between Holt and Buchanan," Boston Consulting Group said in a statement to NBC News.

"We provide strict guidelines for senior consultants to disclose any conflicts of interest," Boston Consulting said, adding that it has terminated Holt's non-disclosure contract.

Boston Consulting Group said Holt is a recognized industry expert who works for the group part-time and pays by hour.

"She was not involved in establishing the project or negotiating any contract terms and is not expected to lead any part of the project," the organization said.