Council Tax Benefit Advice

Hello,

I am a single mum and I have a son who goes to University now. I had a letter from the Census District Council to say that my council tax benefit has been suspended because I do not receive child benefit. As a matter of fact I am still receiving child benefit and they are now asking me for proof of my sons student status, is there any reason for this? They are also asking for my payslip and my latest tax credit award letter.

Please tell me as to why they're asking for my sons student status? Does it make a difference to them?

Thanks,