Is it illegal to resell the company's products to earn the difference?

Illegal.

According to the French Open, the actor took advantage of his position to increase the price of his own business, operated in the name of a privately established company, concealed the truth from his own unit and his counterparty, and defrauded the difference for personal ownership, which constituted the crime of duty embezzlement. The crime of embezzlement can be complained to the industrial and commercial bureau, and the public security organ can be requested to file a case for investigation, or a lawsuit can be brought to the people's court with jurisdiction.