Price adjustment if the cart total exceed given value.

functions.php

add_filter( 'woocommerce_package_rates', 'wf_rate_adjustment_if_cart_total_exceed', 10, 2 );
function wf_rate_adjustment_if_cart_total_exceed( $available_shipping_methods, $package ) {
	$minimum_cart_price_to_adjust = 30; //give value here
	$shipping_services_with_price = array(
	     'wf_shipping_ups:01' => 0,   //give shipping service with adjustment price in percent.
	    'wf_shipping_ups:02' => 0 
	);

	$cart_total = WC()->cart->cart_contents_total;
	
	if( $cart_total > $minimum_cart_price_to_adjust ){
		foreach ($available_shipping_methods as $key => $value) {
		    if( array_key_exists( $key, $shipping_services_with_price ) ){
			$available_shipping_methods[$key]->cost *=  $shipping_services_with_price[$key] ;
		    }
		}
	}
	return $available_shipping_methods;
}