Using comma as separator in Forms

I live in The Netherlands and we use a comma as a decimal separator. However when I use Microsoft Forms it doesn't accept the comma, it removes it. See below.

Both Windows and Google Chrome have the right regional settings, namely Dutch. 

The strange thing is that when I do the same in a Sharepoint list, it works correct. So the problem seems to be with Microsoft Forms.

Any ideas anyone?

ps I have also set the primary language to Dutch.