It’s not in this forum.
You could open the file in another PDF viewer to test whether it is a bug in the PDF viewer or an error in the PDF file (which is not an Adobe format if LayOut follows standard PDF/A). But having a viewer without bug won’t help if your clients don’t use the same viewer.
Reports on the internet mention often bugs in Microsoft’s Bahnschrift (which is not even their own design, just their new implementation of it). It appears only one of the included font style displays right (try to switch to Light, not Regular), and the others have wrong widths.
You could also to replace the font with a shape-identical one. There exist multiple implementations of the original DIN 1451, like d-din or http://automatsvet.cz/traffic/.