[SOLVED] net price + vat: opencart sums up to wrong order total

My opencart is version 3.0.3.6
I can not add the correct prices with decimals. Example: for a product my final price is 20 €. Without tax (24% in Greece) is 16.13 €. But site does not accept it and changes automatically to before tax to 16,00 – final price 19.84 €.
Is there anybody who can help me to solve this problem?
Thanks in advance
thanos

Guess you did not set the currency correct.
Define Euro with 1 (Value) and as standard Currency.

The currency is correct. Euro is the only standard currency.
My problem is that the opencart does not accept the correct calculation in decimiles after adding the tax 24%. Just whole number.
For instance if price must be 20,10 €, opencart is changing to 20 €.
I tried with more decimiles, like 20,10000 but is not either workable.

Now I am a "bit" confused .
Once you write 16,13 as net value, then yo uset 20.1 > as what?

Just to clarify, I have tested that just for curiosity right now (OC 3.0.3.6).
Tax is 24%
Net product value is 16.13

Now, in the shop it displays 20.00 as GROSS, and 16.13 as NET.
100% correct.

So I really don't know what you are using or how you have the checkout modules defined.
And what I am missing what Template you are using, and maybe additional extensions installed?!

Language -> Your_Language folder -> your_language.php: You are used to use ',' as decimalpoint in valuta, e.g. 16,31 ??

Thank you both for your kind help.
I fixed it, it was my mistake ( I used on prices "," instead of ".")
It was so simple, but it is my first opencart development and I did not manage to find the solution.....
thanks again