Hi Jose,
Greetings from Syncfusion support.
The problem occurred because of enabling IncludeHeaderRow property. We would like to inform you that, this is an already known issue and we have fixed this case internally. This is expected to be rolled out in our Volume 1, 2021 SP release which is scheduled to be released in the month of May 2021.
Until then we appreciate your patience.
Regards,
Renjith R