to add the Points and Rewards discount also id the option "Disable with other coupon" of Dynamic Discount is active:

functions.php

<?php

if ( function_exists( 'YITH_WC_Points_Rewards_Redemption' ) ) {
	add_filter( 'ywdpd_disable_with_other_coupon', 'ywdpd_disable_with_other_coupon' );
	function ywdpd_disable_with_other_coupon() {

		if ( ! WC()->cart ) {
			return false;
		}

		$cart_coupons = yit_get_applied_coupons( WC()->cart );

		foreach ( $cart_coupons as $coupon ) {
			if ( YITH_WC_Points_Rewards_Redemption()->check_coupon_is_ywpar( $coupon ) !== false ) {
				return true;
			}
		}
	}

	if ( ! function_exists( 'yit_get_applied_coupons' ) ) {

		function yit_get_applied_coupons( $cart ) {
			if ( version_compare( WC()->version, '3.2.0', '>=' ) ) {
				$coupons    = array();
				$coupons_id = $cart->get_applied_coupons();
				if ( $coupons_id ) {
					foreach ( $coupons_id as $coupon_code ) {
						$coupons[] = new WC_Coupon( $coupon_code );
					}
				}

			} else {
				$coupons = $cart->coupon;
			}

			return $coupons;
		}
	}
}