Hi
I am trying to add a combo box on a canvas app to allow users to show and select select multiple choices from, a SharePoint list column.
The list is called Board Members and has a multi-select column called Membership.
In the [Items] field I have tried :

but as you can see it just returns [Table] and the dropdown just shows nothing next to the checkboxes.

If I place my cursor at 'Choices' It does show the values in the expression editor preview:

I have also tried:

But now it shows blank entries at runtime:

The reason I am using a Combo Box is because I want to be able to use Patch instead of using the a form.
Can anyone please advise? It's driving me nuts.
Really appreciate any help that can be offered.