This will be lower case issue.
Need to delete failed request from dso and do the correction psa level.
Have you tried to change your record at psa?
You can edit to S.MACK and save.
reload to dso and try to activate it.
if you want go with lower case letters then at info object level you can select lower case check box on general tab.
or at transformations you can convert lower case to upper case.
Thanks