is this a single vehicle accident, or is there another party at fault?
if you are NOT at fault, then FBD will arrange for car to be repaied at THEIR nominated repairer and will seek recovery of their outlay from the other motorist.
If you are at fault then the procedure is similar, but they obviously will NOT be able to recover from anyone.
You must notify them and go to their repairer to get car hire benefit.
As other poster has said, your NCB is not affected, but you may find it difficult to get a quote from another insurer at next renewal as other insurer will deem the claim to be a claim.