Grafana autocomplete graphs

Hello people, everything fine?
I’m new to grafana but already setup a couple dashboards with Zabbix. The problem is: sometimes zabbix is getting some null data, but grafana is “autocompleting” the graphs, so, when I see my dashboards I cannot visualize when I had a problem. Is there a way to disable that?

Obs: The weird part is that it only happens in especifics timestamps, if I want to see 12 hours, the blank space is there, but if I select a closer view, like 3 hours, the gap has been filled.

Here are some pics of the sam graphs but in different timestamps: