Time Range Controls

I use Grafana as visualisation tool for all metrics of my Prometheus datasource.
I have a question concerning time ranges. I get Cloudflare bandwith (cached+uncached bandwidth) metrics. When I want to display graph and Total value of this metric cloudflare_pop_bandwidth_bytes in prometheus the value it gives for sum(sum_over_time(cloudflare_pop_bandwidth_bytes[24h])) is right just like for 1h, 24h and 30d, but in Grafana dashboard the indicators are different for the same time range.
For example, when I select last 30 days on Time Range panel in Grafana it returns this value 219.30 TB which is less than it is for 12h or 24h (223.05 TB), which is not possible. Also, when I compare Total value in Prometheus and Grafana, the values are different.
This is my query and value per Petabytes in Prometheus for 30 days:

And this is the graph for same metric in Grafana for last 30 days:

Thanks in advance.
Looking forward to your answer.

You need to use the function sum over time with a range vector same as step [$__range]

Thank You very much!