https://techcrunch.com/2020/03/06/facebook-face-masks-coronavirus/

On Friday, Facebook announced that it would further attempt to limit coronavirus-related chaos on its platform by banning commerce listings and advertisements for medical face masks.

“We’re monitoring COVID19 closely and will make necessary updates to our policies if we see people trying to exploit this public health emergency,” Facebook Director of Product Management Rob Leathern said in an update on Twitter. “We’ll start rolling out this change in the days ahead.”