Facebook has issued a ban on cryptocurrency based ads. The new rule was imposed on Jan 30, 2018.
A post published by Rob Leathern, the product management director of Facebook says
Two of our core advertising principles outline our belief that ads should be safe, and that we build for people first. Misleading or deceptive ads have no place on Facebook. We’ve created a new policy that prohibits ads that promote financial products and services that are frequently associated with misleading or deceptive promotional practices, such as binary options, initial coin offerings and cryptocurrency.\
The above picture indicates new Facebook policies against Cryptocurrency ads.