Disable 'flat_rate' shipping

Hello,

Today updating WC to the latest version.
There are new shipping methods.

When buying for more then 100€ then is free shipping.
In the previous version, i have a solution for this.
I place this code in the functions.php for hiding the ‘flat_rate’ shipping:

function hide_shipping_when_free_is_available( $rates, $package ) {

 	// Only modify rates if free_shipping is present
  	if ( isset( $rates['free_shipping'] ) ) {

  		// To unset a single rate/method, do the following. This example unsets flat_rate shipping
  		unset( $rates['flat_rate'] );

  		// To unset all methods except for free_shipping, do the following
  		$free_shipping          = $rates['free_shipping'];
  		$rates                  = array();
  		$rates['free_shipping'] = $free_shipping;
	}

	return $rates;
}

In the latest WooCommerce version this function doesn’t work anymore.
Who can help me find a solution for this?
(I think it’s another hook for flat_rate shipping)

Christophe

https://wordpress.org/plugins/woocommerce/