Child benefit

Ladies has anyone had an issue with there child benefit just stopping. I realised a few months ago my bank account seemed low but put it down to maybe over spending over Christmas but I recently got online banking and noticed my child benefit hadent gone in so when I went on my banking to check it haswnt been paid since October so that's about 3 months I haven't been paid. My kids are only 8;6 and 3 so would have no reason to stop it. Also we aren't earning over the threshold. Has this happened to anyone else will they backdate it. I'm going to ring tomorrow and see what the issue is. Also if anyone had any insight to what information I'll have to provide when I call so I have it all there that would be great thanks xx