I believe it's normal behavior of city's fuel guage, maybe something to do with fuel tank position (below front seats and gear lever) it does need at least half tank top up for fuel guage to move if you go below last quarter my 2021 city 1.3 manual does the same. Small 1000-2000 topups don't make a difference and 3000 it may not show up immediately but after driving for sometime.
So when topping up 10 liters or less, multiply the liters by 10 to get the least amount of km the vehicle will run on topped up fuel.
Though mine does 12-14 in city and more on long route