Triple click does not work anymore

If I draw f.e. a rectangle, I can’t tripple or double click it anymore in order to form a group. It just selects the plane, nothing more. Does anyone have experience with this?

Check your mouse and/or reboot your computer. SketchUp 2017 Make hasn’t changed for more than three years so there must be an issue with the hardware or drivers on your end.

Thanks for your answer, you are right, it is something with my computer, it comes and goes.