Disable Paypal during Checkout

Possible. Add this snippet to your site –

add_filter( 'wcfmmp_is_disable_multivendor_checkout', function( $is_allow ) {
	return 'no';
}, 750 );
add_filter( 'woocommerce_available_payment_gateways', function( $_available_gateways ) {
	$vendors = array();
	if( function_exists( 'is_checkout' ) && is_checkout() ) {
		foreach ( WC()->cart->get_cart() as $cart_item_key => $cart_item ) {
			$cart_product_id = $cart_item['product_id'];
			$cart_product_author = wcfm_get_vendor_id_by_post( $cart_product_id );
			if( $cart_product_author && function_exists( 'wcfm_is_vendor' ) && wcfm_is_vendor( $cart_product_author ) ) $vendors[$cart_product_author] = $cart_product_author;
		}	
		if( !empty( $vendors ) && ( count( $vendors ) > 1 ) ) {
			unset( $_available_gateways['paypal'] );
		}
	}
	return $_available_gateways;
}, 700 );

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Is it still Paying the Vendor directly then?

And do i use this code with the Paypal direct payment Plugin or without it?

NO, it’s not depending upon WCFM Direct PayPal addon.

Is it still Paying the Vendor directly then?
– Yes, for PayPal payment.

Okay so i added the Code, it disables Paypal as soon as I have more then 1 Vendor but if i there is only 1 Vendor i still can’t pay because I get to a Paypal website that just says: “Unfortunately a system error has occurred. Please try again later”. I can see that there is a new unpaid Order in the Vendor Dashboard and the Vendor also added his paypal Email-Adress.

What is the meaning of this Error Message? There is nothing in the logs

Where are you getting this message?

At your site or at PayPal during payment?

At the Paypal site

Well, then PayPal account has some issues.

Is vendor’s PayPal account is a business account?

It should be since they have their own Webshop and use it there aswell.

OK. Then please contact PayPal support.