How to return the difference value from array of objects?

Here is the item1 data:

const item1 = [
  {
   
    "proposedWaterClosets": 2,
    "proposedToilets": 3,
    "noOfWaterClosets": 3,
    "noOfToilets": 3
  },
  {
    
    "proposedWaterClosets": 2,
    "proposedToilets": 3,
    "noOfWaterClosets": 3,
    "noOfToilets": 2
  }
]

Here is the item2 data:

const item2 = {
    
    "proposedWaterClosets": 2,
    "proposedToilets": 3,
    "noOfWaterClosets": 3,
    "noOfToilets": 3
  }

I want the output to be like this which only return the difference value

expected output:

[{ "noOfToilets": 3 }]

Here I am having issue , I am getting which the value is same .. here is my approach using map and with the help of if condition, the thing is I am getting the output which is equal … Any suggestions would be appreciated

 const result = item1.map((it) => {
    if (it.noOfToilets !== item2.noOfToilets || it.noOfWaterClosets !== item2.noOfWaterClosets) {
      return { oldToilets: it.noOfToilets, oldWaterC: it.noOfWaterClosets };
    }
  });

getting output: [{oldToilets::2,oldWaterC:3}]