Hi, sorry to hear that you are having problems with your cookmaster, I've had a quick look at their site, and you can download the manual from there, also on a quick flick through the manual I noticed that it said 'the main oven will not work until the clock is set', so it could be just a case of setting the clock, I hope this is of some use to you, the link is below if you need it :)
Dimensions (cm): (H)90.0 x (W)100.0 x (D)60.0 Manufacturer Warranty: 1 Year(s) Hob Type: ... more
Gas Oven Type: Gas Main Cavity Type: Conventional Oven Number Of Ovens: 2 Number of Functions: 1 Stay Clean Liners: Yes Removable Inner Door Glass: Yes Slow Cook F...