Bug in German Localisation; Loan

When you want to get a annuity loan from someone and edit the interest rate or the inital repayment rate in the German loc (Firefox used), it says that you have to choose sth lower than 1 / 0.5
It seems that it accepts only numbers with “,” like the German wording. But if you do so it will not create a loan. It closes the process without making one.
Solution for me was to change to the ENG-Loc. Here it worked perfekt with “.” like the english writing for digit numbers