Datamatrix code looks different as expected

I am currently trying to migrate my c# app from using Printdocument to ZPL. Ony my label I hava a datamatrix code (26x26, ECC 200, Data BASE 256). Previously I rendered the Code using ZXing.Net. Using ZXing the resulting datamatrix code looks as following:


Using the online ZPL viewer my result looks exactly the same:…

Nevertheless when I print the label on my 105SL the result looks different






Does anybody know why my printed result looks different orwhat I need to change to get the expected result?