Why can´t I do the participant upload?

Have you checked if the services (accommodation/number of participants) match the booked services? If you want to increase the benefits, you must first enter the raises and let it confirm by the hotel, then you can make the upload again.

Furthermore, the excel must only contain one spreadsheet and must not contain empty cells (cells that previously contained something).

Please also make sure that the headings fit after you uploaded the excel into the system.