Pushing data into array instead of new entry

hi everyone, I am attempting to make favourite functionality in repeater. instead of creating new entry for each userid and item, I was trying to push all items into a field say"itemsmarked" in a single entry for each user. I tried so many ways but I cannot get it done. any suggestion to achieve this? sorry for my limited English.

Karl

let findArray = [];
 $w.onReady(function () {

     $w('#repeater1').onItemReady(($item, itemData, index) => {
         wixData.query("UserSubmission")
             .eq("userId", wixUsers.currentUser.id)
             .find()
             .then((results) => {
                 let items = results.items;
                 for (var i = 0; i < results.items.length; i++) {
                     var array = items[i].itemsmarked;
                     findArray.push(array);
                 }
                 check();

             })

         $item('#unmarkedButton').onClick((event) => {

             let toInsert = {
                 "mark": itemData._id,
                 "userId": wixUsers.currentUser.id
             }
             wixData.insert("UserSubmission", toInsert)
                 .then(() => {
                     $w('#dynamicDataset').refresh();
                     $item("#unmarkedButton").hide();
                     $item("#markedButton").show();
                 });

         });
         $item('#markedButton').onClick((event) => {
             wixData.query("UserSubmission")
                 .eq("userId", wixUsers.currentUser.id)
                 .eq("itemsmarked", itemData._id)
                 .find()
                 .then((res) => {
                     let item = res.items[0];
                     let toRemoveId = item._id

                     wixData.remove("UserSubmission", toRemoveId)
                         .then(() => {
                             $w('#dynamicDataset').refresh();
                             $item("#unmarkedButton").show();
                             $item("#markedButton").hide();

                         });
                 });
         });
     });
 });

i assume you want to push them all into a array ?
Or what do you try to do with into a field?

As i understand wix and its api`s you need diffrent items for repeapters to work.