Mac Mini Fusion drive lost

Hi,

If someone could help me with the following problem it would be very much appreciated.

I have a 2012 Mac Mini with a 1 GB Fusion drive which has disappeared, I can only see the SSD. I installed Win 7 on it back in the day using Bootcamp which I suspect is the problem.

I have tried using the disk utility but it does not recognize anything apart from the SSD.

Any suggestions?