How did it Happened Facebook?

Does everyone experience this? This is actually the Facebook account of our company, and it seems like some unknown email had been put as one of the email contact. Why and How did it happened this way? Facebook might be not the best or trustworthy option in terms of Privacy. I think this is not a glitch or maybe a program error. I think Facebook has lost control over their system as to who access their personal information, but it's my opinion though.