The problem is that you are trying to import 99 times the same value.
Please see this demo in which I am importing different values.

In the demo, the upper combo box is filled with a for loop
and the second combo box’s data is being loaded with the dataSource property

Here is a link for its API: https://www.htmlelements.com/docs/combobox-api/

Best Regards,
Svetoslav Borislavov

Smart UI Team