Has any body experienced their odometer suddenly losing miles then clocking up miles at extra fast pace?

Well I’m at a loss to know what’s going on . My Suzuki Grand Vitara 58 plate had 83 k miles on the clock , when the DPF warning light came on the other day, I noticed the mileage reading was 30 k????? It had wiped over 50 k off the screen??? I also notice that it is clocking up miles extra fast . Ye...