After upgrade to EHP6 from EHP5 in ECC6 we had corrupted screens where some fields got currupted. Some fields went missing and were sitting on top of other fields in the screen. The problem got resolved after re-generating the screens. Issues like this happen most likely after an upgrade.
You need to regenerate the carrier dynpros by following the below listed steps:
1. Transaction BUSP
2. Select ‘all Screens’
3. Press F8
Once the programm is finished, the issue should be solved.