Hi all,
I am experiencing an issue with the Modern UI.

When I click the ADD & CLOSE button, I receive the following message on the screen.

How can I resolve this?
Here is the relevant HTML/TypeScript code for reference:
export class BZLines extends PXView {
@columnConfig({ allowSort: false, width: 60, allowCheckAll: true }) Selected: PXFieldState;
InventoryID: PXFieldState<PXFieldOptions.Disabled>;
SiteID: PXFieldState<PXFieldOptions.Disabled>;
InventoryID_description: PXFieldState<PXFieldOptions.Disabled>;
OpenQty: PXFieldState<PXFieldOptions.Disabled>;
Quantity: PXFieldState;
}
<qp-panel id="BZLines" caption="Items Selection">
<qp-grid id="grid-BZLines" view.bind="BZLines"></qp-grid>
<footer>
<qp-button id="CstButton85" caption="ADD & CLOSE" dialog-result="OK"></qp-button>
<qp-button id="CstButton86" caption="CANCEL" dialog-result="Cancel"></qp-button>
</footer>
</qp-panel>
Thank you for your help.