I canceled a trip with German Railways and they gave me a "voucher" with the value of the trip. If I use this coupon to buy something of less value, I can use the rest of the coupon again?
In the website, they say
If you combine voucher and eCoupon and the value of the vouchers exceeds the ticket price, unfortunately, we can not issue you a residual voucher for the remaining amount.
I can get a "Residue Coupon" when I just use a coupon and not a coupon together with an eCoupon.