Amazon did sent a letter to the members of Congress on Friday over look into the company’s third-party seller practices but the House Judiciary Committee Chairman Jerry Nadler has called out the giant e-commerce company in his tweet stating the letter is “Unacceptable”.

Amazon had denied the claims that it’s against it’s policy and in the letter said it would investigate the violation. The report came from the Wall Street Journal which stated that Amazon regularly use information from it’s sellers to create the company’s private-label products with which the company can have a competing product up right against its competitors

“Members from both parties have serious questions about Amazon’s business practices and its honesty with the Committee,” Nadler tweeted. “We will not permit stonewalling of our investigation, by Jeff Bezos or anyone.”

Meanwhile, Amazon vice president of Public policy, Brian Huseman wrote in a letter to the congress that the company is “prepared to make the appropriate Amazon executive available” to the committee but didn’t mention the company’s CEO, Jeff Bezos. Huseman added that the company was investigating the claims made in the WSJ article.

“We disagree strongly with any suggestion that we have attempted to mislead the Committee or not been cooperative with the investigation,” Huseman wrote in the letter, which was addressed to Nadler and members of the House antitrust subcommittee.

Members of Congress have threatened to subpoena Bezos, an idea that Rep. David Cicilline (D-RI), chairman of the antitrust subcommittee repeated in a tweet on Friday.

“No one is above the law, no matter how rich or powerful,” Cicilline tweeted. “We have asked Mr. Bezos to testify before the US Congress about Amazon’s troubling business practices and false statements, and we expect him to do so. Whether he does so voluntarily or by subpoena is his choice.”