Sheen said that he had unprotected sex with some sexual partners after his diagnosis, but had done so safely to ensure that none would contract HIV. He also told Lauer that he had informed his sexual partners of his diagnosis prior to engaging in sexual relations. That has raised questions among the public, and has been contested by at least one former sexual partner.
https://www.pbs.org/newshour/health/4-things-to-know-about-charlie-sheens-hiv-diagnosis