Reporting of anomaly in a decimal or currency section

When you set a certain amount of number after the point, ex 3 decimal, if you insert the fourth decimal number, the first of them is moved to the integer part.
For example, if you set 3 ciphers and insert 10,2251 the system inserts it as 102,251 instead of blocking the whole number.
Some customers underline the problem
Is there a solution or can you provide to resolve it?
Thanks