Mismanagement of funds by partner

After drawing up a contract, I invested in a company, but the company's partner used some funds without my knowledge or approval. I want to reduce that amount from his investment while sharing the profits but he doesn't want to do that. I drew up another contract stating the ROI for the amount he used to be the project ROI while sharing profits. He says no. The original agreement doesn't have any clause regarding the mismanagement of funds. what can I do now?