Hackers.
I had two using my friends' dormant accounts to contact me. The minute I wrote Hmong to them, they could not write anything back in Hmong but tried as much to respond to me in English as possible to avoid writing in Hmong. They would change subject and ask about how my family was doing instead. Then they would go off into some deals about sending money to a trusted friend of theirs for help on getting more money.
The last person I wrote to in Hmong continued back in English. I already gave him/her one signal: you can't write Hmong, that decides this for us.
They still wrote back. I blocked them right away.
They prey on dormant accounts. If you haven't used our account for a while, they can get it by just telling Facebook they've forgotten their passwords, etc. Then they would be able to access your account for a time. If you know about it, you can get your account back, because if you remember your original password and username, Facebook will restore those to you over any new password someone else may be using from a location the original password wasn't in. I had to take that route to get mine back one time.
