Hi Jens,
Thanks for contacting Syncfusion Support.
We have checked your query and prepared sample as per your code example but we are unable to reproduce the problem at our end.
Refer to the sample Link:-
Refer to the screenshot:-
We need some more additional details to find the cause of the issue. Share us the following details.
- In which scenario the issue gets reproduced. ( replication procedure for this).
- Have you enabled any property for the first column to reproduce the issue.
- If possible replicate the issue in the above sample and revert us back.
- Does this issue occurs while using any Locale?
Regards,
Farveen sulthana T