"Summary bar" do not work on every grid


In IOS, the Summary Bar work OK when I open my base with a view on grid A. But when I change for the grid B the Summary Bar stop to calculate the results. The words: sum, avg, min, max etc…appear when I pull down the screen but with no value beside. To resolve the problem, I need to close this base and re-open it on grid B. At this time the Summary Bar on grid B work OK but the grid A stop to work if I choose it again.