Wrong labels

[JSchatral]

Hello everybody,

For a payment process, I have added two items. As a text for subtotal I get in German language 
but total amount (Gesamtbetrag) displayed. 
The overall subtotal text will be the text Subtotal - that's not correct...What am I doing wrong? In Germany, the total amount is always 
subtotal plus tax = total amount. (Zwischensumme plus Steuer = Gesamtbetrag)

What can I change to get it displayed correctly? 
Thank you - Greetings from Germany