UdoVR:
OUCH!!! beginner's mistake I hope? didn't notice the odd/even thing, also not in the documentation.
Well, that's how it always goes with those connectors. They go with ribbon cable and when that is connected, the numbers in the ribbon are sequential.
That module has "1" and "16" indicated, but did not tell you which "2" was, however the datasheet does in part 4. 