How can I ensure that a Retrofit function is working only once

I have an app with different API operations made with retrofit. Unfortunately, the API I am using doesn't have an update function so instead of updating, I am currently deleting, and adding with updated values.

This solution works OK when my update clicks are more than half a second apart, but when I click faster It causes duplications.

I am using Data Binding and MVVM. So, function call route is as following: XML -> Fragment (Adapter in this case) -> ViewModel -> Repository

fun updateCartItem(cart: Cart) {
    apiService.deleteCartItem(cart.cartFoodId,cart.orderUsername).enqueue(object: Callback<CartResponse> {
        override fun onResponse(call: Call<CartResponse>?, response: Response<CartResponse>?) {
            apiService.addFoodToCart(
                cart.foodName,
                cart.foodPicture,
                cart.foodPrice,
                cart.foodQuantity,
                cart.orderUsername
            ).enqueue(object: Callback<CartResponse> {
                override fun onResponse(call: Call<CartResponse>?, response: Response<CartResponse>?) {
                    fetchCart(cart.orderUsername)
                }
                override fun onFailure(call: Call<CartResponse>?, t: Throwable?) {}
            })
        }
        override fun onFailure(call: Call<CartResponse>?, t: Throwable?) {}
    })
}

I tried to add @Synchronized annotation to my function, but it didn't help.

Basically what I need is a way to ensure my update function is working only once.