Question about document opening pdf?

On my new laptop, I often have the problem that the open documents disappear pdf behind the taskbar and then I try to push down the taskbar, which does not work. Also by opening the new pdf

the pdf disappears behind the T. Bar. The download does not work either. I urgently need help with the solution, because I print out online shipping labels that disappear just behind the T. Bar and the pdf can only be clicked once for printing then it is locked.

Restart the laptop

or

Uninstall and reinstall the pdf program

Deinstall the program and do it again drauf. Or download another program to open PDF.

Try SumatraPDF, if you reinstall anyway.

If, like me, PDF opens just for reading, it is pleasantly easy and fast.

I need it to print labels or print invoice

Of course this is synonymous, only PDF do not edit.