how can i fix my immobilser on my zafira its stuck on and wont come off?

hi all went to start my zafira this mornin and it wouldnt start called out the aa and they reckon the immobilser is stuck on have rang vauxhall and they are gona make me bankrupt with the price they gave me does anyone have any ideas on how to bypass it or turn it off plllleeeeeaassssseeeeeee