The issue of midi channel failure

Hi, when i want to edit midi channel (double click on track), all sounds stop down and only midi channel plays. it happened 2 days a go and i can’t fix it. Pls help

Note; kontakt and ez drummer is same
i backed up my pc a week a go.

First, click the gear icon to the top right of the Key Editor and make sure that “Default Items” (the first option) is enabled.

Click the S button to the top left to deactivate Solo Editor. The button will become grey.