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Co-authored-by: deboragracio <63159404+deboragracio@users.noreply.github.com>

Author: MaximilianFT

HOWTO_01_Payment_csharp/README.MD

@@ -40,7 +40,7 @@ In many payment vendor apps, it is possible to add a tip to the payment amount.
 8. The **fiskaltrust** InStore App / POS System API reports the following in the payment response (see also an example on the POS System API docs):
   - 2 pay items
   - Pay item 1: The total paid amount with the receipt -> 12€
-  - Pay item 2: The tip with negative amount -> -2€
+  - Pay item 2: The tip with a negative amount -> -2€
   - sum of the 2 pay items is the original requested amount of 10€
 
 NOTE: The tip can be calculated by simply subtracting the requested amount from the paid amount (12-10 = 2€ tip) or alternatively from the 2nd pay item (-2 * -1 = 2€ tip).