In ionic, ion-datetime in ion-item cover to all item. I think date time didn’t exist any properties for this. You must edit css or js for this. Just like this:
The ability to trigger the datepicker using a (click) event. If you were to display the date using some other means and have a button using the method mentioned in the link you might get away with it.
ion-datetime in ion-item will create a button cover the hole ion-item and z-index value set higher than any item in ion-item. You click to ion-item, actually you click to button in ion-datetime and it opens to ion-datetime. If you set witdh to auto, button will not cover all ion-item and you can click any item in ion-item.
Solution 2: You can set ion-datetime position:relative and button covers to just ion-datetime. I think this is a better solution for you: