New World Oven Timer Fault

I own a New World E70DOa double oven which has developed a timer fault. The timer display disappears or partly disappears. Sometimes the oven will contiue to work and sometimes it wont due to the timer fault.

If I kill the power for a short time I can reset the clock and all is well for a time then the timer goes faulty again.

I take it the timer needs replaced? How easy is it to source a replacement and more importantly who easy is it to replace? (I’m fairly competent at these sort of things)

some advice please!