How do I update a single array item that's being displayed in a List with a ForEach loop?

I have my list, and a ForEach that itterates over my array of custom items. Inside the ForEach I have a button, and that button should update the specific array item that's being shown on that line.

Here's my current code, it throws an error on the line item.LastTouch = Date.now: "Cannot assign to property: 'item' is a 'let' constant"

            List {
                ForEach(contacts.items) { item in
                    HStack{
                        VStack(alignment: .leading){
                            Text(item.name)
                            Text(item.company)
                            Text(item.lastTouch.description)
                        }
                        Spacer()

                        Button(action: {
                            item.lastTouch = Date.now
                            //print(item.lastTouch)
                            //contacts.sort()
                        }) {
                            Image(systemName: "checkmark.seal.fill")
                                .resizable()
                                .frame(width: 50,height: 50)
                        }
                        .buttonStyle(PlainButtonStyle())
                    }
                }
                .onDelete(perform: removeItems)
            }

If your contacts.items comes from an ObservedObject or a StateObject, you can use a binding to the individual items in your array:

ForEach($contacts.items) { $item in
   ...
}

Change your item properties from 'let' to 'var' and you will then be able to modify them.