Issues with gauge's max/min values


I’m currently using gauges to show our users the current number of total connections in their SonicWALL but, for whatever reason, I’ve encountered an issue and I’m not really sure how to fix it other than adding more threshold values.
Apparently there’s still small red line at the left side of my gauge, even though the max/min and threshold values have already been modified, the value 100 keeps showing up whereas it should be 0:

Aside from adding more threshold values, which does fix the issue but our clients are only really interested if the number of current connections is greater than 80% of the maximum number of connections, is there any other way to fix it?

Currently using Grafana v5.3 and using the Zabbix pluggin.