How do I use whole number data validation?

I have set data validation for a cell to “Whole numbers” (sorry, don’t have the points to upload screenshots, so here’s an imgur link). Typing “100” into the cell, I get an “Invalid value” error message (screenshot here). What am I missing?

Here are the version details:

Build ID: 1:5.1.6~rc2-0ubuntu1~xenial2
CPU Threads: 12; OS Version: Linux 4.4; UI Render: default; 
Locale: en-US (en_US.UTF-8); Calc: group

You have set the valid range of whole numbers from 0 to 0, so any whole number from that range will be OK.

If you need to allow any possible value, then you can, e.g., use “not equal to - 0,5” (i.e., use non-integer), so that the value will not restrict your whole numbers.