My suggestion is to look around the forum. There are a ton of threads on here about what to do in this situation, and yet every day multiple people open up the same basic thread question. The workarounds for this are plentiful - > please put in the effort to search the forum at least a little before posting a thread.
Most people are likely avoiding bans altogether with a mixture of shorturls, and respecting facebook posting limits. You guys are pulling wicked newbie moves on this one. Check the limits - you likely triggered facebook internal filters resulting in manual review leading to domain ban. Or you did worse and simply flooded the link all over the FB world. You guys should read all the threads about account bans, all the threads about how to post a domain multiple times without getting a ban, and all the threads about the basic limits of posting on facebook.
At that time you should be far better prepared to handle this situation. In the meantime, the others are correct - > it's time to get a new domain if you want to continue on facebook in this manner. Also - > don't duplicate the mistake you made that caused this domain to get banned.