how do i fix my diplomat oven, model 700GA, ADPO540?

I HAVE A DIPLOMAT OVEN AND HOBB THAT WAS ALREADY IN MY FLAT WHEN I MOVED IN SO I DONT KNOW WHO TO CONSULT REGARDING FIXING IT. THE HOBB IS OK BUT THE OVEN JUST SWITCHES ITSELF OFF ALL THE TIME AND LOSES POWER. IF YOU TURN IT OFF AT THE WALL AND LEAVE IT OFF FOR A BIT IT THE POWER COMES BACK ON THE DISPLAY BUT YOU CANNOT RELIGHT THE OVEN. WHEN IT EVENTUALLY COMES BACK ON IT MAY WORK FOR ABOUT HALF AN HOUR AND THEN SWITCHES ITSELF OFF AGAIN. I HAVE NOTICED THAT IT GETS EXTREMELY HOT AROUND THE DISPLAY AND THE KNOB AREA. SO HOT IN FACT YOU CANT TOUCH IT! ALSO I THINK THE OTHER DAY AS IT WAS GOING OFF IT CAME UP WITH AN ERROR 69( NOT SURE BECAUSE IT WAS THAT QUICK). PLEASE CAN YOU HELP ME BECAUSE I AM STARVING TO DEATH!!!