Different number at different periods

Hi there,
I’m running a piwik 3.0.4 and I don’t understand the analysis:
I download a file from my page and have one hit in piwik.
Everything is ok.
But if I change the period to “year” or “greater 2 month”,
piwik says “There is no data for this report”

I’m shure there must be a hit. The download is available for 5 month.

Where is my fault?

Michael