Hi Dimitar ,
To better assist you, we would like to inform you that the card header is determined by mapping the HeaderField property, which is set within the KanbanCardSettings. Please note that the value assigned to HeaderField should be unique to avoid any duplication is the behavior.
Documentation reference : https://blazor.syncfusion.com/documentation/kanban/cards#header
In your case, since you do not wish to display the ID as the card header, you may consider disabling the header by setting the ShowHeader property to false. By default, the Kanban board enables the ShowHeader property to display the header at the top of each card.
Furthermore , if you'd like to display custom content in the card, you can use a card template to tailor the appearance as needed. Please refer to the documentation below for further guidance:
https://blazor.syncfusion.com/documentation/kanban/cards#template
If the information provided does not fully meet your needs or if you have any additional questions, please feel free to share more details with us. We are here to help you further.
Regards,
Mallesh R