I had exactly the same case. Unfortunately, this product is not fit for use and the review does not mention it.

I cannot believe that not one review mentioned one of the biggest cons of this watch so I had to find it out after the purchase.
This watch gathers all the data for 24h and in case you don't manually sync it with the app EVERY DAY at the end of the day, the data will be completely lost the next day.
How is that not relevant for a review?
This info would have been a deciding factor in me not purchasing this watch and getting frustrated finding it out on my own after reading dozens of "reviews".

I purchased smart band few days back. My main purpose was to track calories burnt after workouts.it's giving incorrect data. It was too high. 60 mins i burn 400-500c however its shows 1000 plus calories. Its not possible. Not satisfied with it.

Hello,
I have purchased this band a week ago and the calories counting is completely off: without the workout mode active, 7k steps are counted as 35 calories burn which is obviously wrong. I have an iPhone 8, can this be the issue? Have you had this yourself and found a solution?

Bought mine 6 months ago on AliExpress for £50. Brilliant watch and had no problems whatsoever! Battery lasts me about 14 days!

I bought a Pro 7 band and immediately had problems with it. It was a total disaster from day one. I have since returned it and will never buy another one, although I have owned XIAOMI mobiles, bands and other products for years. Total rubbish.