Woocommerce – Remove specific shipping method

Hey guys,

I’m pretty new to woocommerce and code snippets, I tried to write a small code to hide a specific shipping method when over 150€, but it doesn’t do anything.
29 is the ID that I got from the form (input value is mondial_relay_point_relais:29).

add_filter('woocommerce_package_rates',function( $rates ){
	$order_total = WC()->cart->get_subtotal();
  
	  if( $order_total > 150 ) {
		unset( $rates[29] );
	  }
  	return $rates;
	}		  
);

I set up the plugin and activated the php code in the public interface. I don’t know if I need to specify somewhere where the code needs to run.

Any help would be gladly accepted.

Thanks!

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