rev dial and petrol dial dnt work on my renault clio mk1 1995 n reg?

on my renault clio 1995, my rev dial and my petrol dnt work, they did work wen i first bought the car but i havent drove it that much as i have not yet got insurance for it etc but the rev dial works wen it likes it just turns on and off whenever but mostly doesnt work, and my petrol dial did work but now doesnt work at all and never turns on and the needle is stuck in the half tank position, so i dnt know how to fix them or is wrong.