Issue: Multiple zero added to invoice

Hello,

I’ve created a product with cost 20,00€ and price €20,00. When I create invoice and add product, those €20,00 are increased by three zeros (000) everytime i click something in the invoice. So, when I setup whole invoice with taxes, etc, those €20,00 becomes 20.000.000,00. I use version 7.1.5 MAX.

Separators are:

for decimals - comma,
for thousands - point

Is there akny know solution for this?

Thanks in advance for answer.