Hi Artur,
Thanks for contacting Syncfusion support. We have analyzed your query and code example. For exporting the chart into excel format, in export function you have to give chart parameters only. Using the export method of the chart, we cannot export the grid into excel format and so it shows the exception. If we pass the chart parameters the export function, export to excel is working fine without showing any exception. Please follow the below screenshot
Could you please provide us the following information.
1. Why did you use grid parameters in the export method instead of chart parameters
2. Do you want to export the grid into excel format
This information will be helpful for us to proceed further.
In the below link, we have attached sample for your reference.
Sample link: https://www.syncfusion.com/downloads/support/forum/123507/ze/Excel_export1879906251
Regards,
Sanjith.