Wrong distance coverage in Apple Health App

Hello team,

I use apple health (via iphone) to track the distance I cover. However, I have noticed a bug. I cover a certain distance, the next day in the records that distance reduces. For example, one day I had covered 10.1 km, but the next day in records it shows me only 6km was covered. This is frustrating because I am supposed to record accurate distance covered through apple health as part of a competition. Please suggest a solution

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