Hello Everyone,
As per the title, I'm having a strange visualization of the Uptime data,
I have Heartbeat monitoring 7 hosts in my house, and the monitor is set to every 30sec.
Now to the weirdness; With the monitor every 30sec, if I set the Date Picker to Last 15 Minutes, I see that every 5th hits, regularly, it shows the bars doubled (14 hits), like it's reading the data twice:
I get to see a consistent data set with Last 750 seconds (with every bars counting 7 hits, correctly):
Before changing to 30sec, I had the Heartbeat ping every 1min and where it now shows the bar doubled, I used to have a "hole" like no data was read.
Either in the Discover tab and in a custom Dashboard I tried to build to prove the data were good, I can see all the entries are pushed correctly every 30 seconds, with no duplicates and I get to see a constant, thus correct, number of hosts (7).
Here's a screenshot of my custom built Dashboard
No in the pic, but the Date Picker here is set to Last 15 Minutes with a Refresh every 60 seconds just like the Default settings for the Uptime App Dashboard.
Is there a way, on my side, to fix this weird behavior?
Thanks in advance! 
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Kibana version: 7.12.0
Heartbeat version: 7.12.0