hide ,show ,collapse in repeater do not work

$w('#listRepeater').onItemReady(($w, itemdata, index) => {
        $w('#button7').onClick(() => {

            let toInsert = {
                "patient": itemdata.title,
                "date": $w('#datePicker1').value,
                "time": $w('#timePicker1').value,
            }
            console.log("pass 1")

            wixData.insert("appointment", toInsert)
                .then((results) => {
                    console.log("pass 2")
                    let item = results; //see item below
                    
                    console.log("pass 3")
                })
                .catch((err) => {
                    let errorMsg = err;
                }).then(()=>{
                    $w('#datePicker1').collapse()  //do not work
                    $w('#timePicker1').collapse()   //do not work
                    $w('#button6').show()            //do not work
                    $w('#button7').hide()             //do not work
                })

        })

    })

it is just a simple insert function but the last part :

                    $w('#datePicker1').collapse()  //do not work
                    $w('#timePicker1').collapse()   //do not work
                    $w('#button6').show()            //do not work
                    $w('#button7').hide()             //do not work

dose not work where is the error in my code ?

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another question if there is an element in a repeater and i want to show it just in the selected item or container without showing in all items or containers in the repeater , can i do that ?and how ?