We want to block buy and sell goods in the decimal quantity for example 1.3 box, 1.2 kg, or 1.4 tons.
It should be 1 box, 1 kg or 1 ton.
It is not about rounding or decimal quantity is reduce to zero.
Another examples are 1 box = 2.5 kg, where the inventory UOM is kg. purchasing and sales UOM are box.
The user have to input 2 box, 4 box, etc. The user can't input 3 box or 1 box etc.
How to block or validate it ?