How to unlock/lock search button on keyboard

Question

I am working on one specific field in form. When I enter the text that has less than 3 letters then should disable the search button on keyboard. When it has 3 or more it should enable it. I tried by accessing UISearchBar property but it doesnt work.

This is what I wrote:

func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
    
    let textFieldInsideSearchBar = searchBar.value(forKey: "searchField") as? UITextField
    
    if itsBicApiCallEnabled && searchText.count >= 3 {
        textFieldInsideSearchBar?.enablesReturnKeyAutomatically = true
    } else {
        textFieldInsideSearchBar?.enablesReturnKeyAutomatically = false
    }
}

I tried by accessing UISearchBar property but it doesnt work.