Mazda Axela 2.2D 2014 Fuel gauge problem

[KKT]

I took off the negative terminal of battery for changing TAU. When I reconnect negative terminal diesel count jumped up around 200Km. Today also I disconnect negative terminal leave it for 20min. When I reconnected, it again jumped up 100Km.

Anyone has a solution to reset fuel gauge to original count.

Thanks in advance.