Discover: alerts-* threshold/value displayed as 0 and not the actual decimal values

It appears Kibana is not displaying the decimal values for threshold/value in the alerts-* indices on the Discover page.

If you navigate to the "Expanded document" and select JSON then you see the actual values

We are seeing this in ELK 8.9.0 and 8.11.1

Please provide info on how to address this.
Thank you,
Kris

Added elastic-stack-alerting

The issue was with index mapping. We were using long type instead of double.