Kibana graph shows wrong value

Hello,
I've made a stacked bar chart as shown below.
a
When I hovered on the particular stack it has shown the count is 8. But when I clicked on the same stack, it has shown the count is 10. See below the reference image.
b
For your reference,

  1. I took 1-day data for the visualisation.
  2. Kibana's timezone is in UTC and my server's timezone is also in UTC
    image
  3. X-axis of the graph represents terms and y-axis represents counts.

Actually the second image shows the correct data i.e. 10. But in the first image its showing wrong value i.e. 8.
Why does this thing happen? Why it shows 8 instead of 10?

Please help!

Can you increase the size of the Terms aggregation that you're splitting by in the first visualization? Try something like twice what you're using now.