Add a custom currency / symbol

wc-add-currency-symbol.php

/**
 * Custom currency and currency symbol
 */
add_filter( 'woocommerce_currencies', 'add_my_currency' );

function add_my_currency( $currencies ) {
     $currencies['ABC'] = __( 'Currency name', 'woocommerce' );
     return $currencies;
}

add_filter('woocommerce_currency_symbol', 'add_my_currency_symbol', 10, 2);

function add_my_currency_symbol( $currency_symbol, $currency ) {
     switch( $currency ) {
          case 'ABC': $currency_symbol = '$'; break;
     }
     return $currency_symbol;
}

Hi Please use code snippet plugin to add this code. https://wordpress.org/plugins/code-snippets/

Hello, I have done so; selected 'Run everywhere'.

But the problem is still the same; same orange alert at top of dashboard page.

And for country I tried my own country,
but also created custom country (world) as well.

Problem still prevalent.