WooCommerce Payments Currency Switcher flags not working

We want use WooCommerce Payments for our website.

We use the widget on the current XSTORE, but the flags related the currency are not shown on XSTORE but neither on STOREFRONT.

We used the below document: https://woocommerce.com/document/payments/currencies/multi-currency-setup/#section-15.

In the code we see

<select name="currency" aria-label="" onchange="this.form.submit()">
	<option value="EUR" selected="">🇪🇺 € EUR</option>
        <option value="AUD">🇦🇺 $ AUD</option>
        <option value="CAD">🇨🇦 $ CAD</option>
        <option value="INR">🇮🇳 ₹ INR</option>
        <option value="JPY">🇯🇵 ¥ JPY</option>
        <option value="NOK">🇳🇴 kr NOK</option>
        <option value="PLN">🇵🇱 zł PLN</option>
        <option value="GBP">🇬🇧 £ GBP</option>
        <option value="SEK">🇸🇪 kr SEK</option>
        <option value="CHF">🇨🇭 CHF</option>
        <option value="USD">🇺🇸 $ USD</option>			
</select>

How can we make it happen that the flags are visible.
We used Chrome and Edge to test and both gave same result.

See snippet
https://prnt.sc/OxjT_0wVlbRW

The page I need help with: [log in to see the link]