Function to control WooCommerce Order Status by User Role

functions.php

<?php

/* Source: https://quadlayers.com/change-order-status-automatically-in-woocommerce/ */

function user_role_order_status( $order_id ) {  
    if ( ! $order_id ) { return; }          
    $order = wc_get_order( $order_id );
    // Change db prefix `wp_` of `wp_capabilities`, if required
    $usermeta = get_user_meta( get_current_user_id(),'wp_capabilities', true );
    // Enter the user role name to apply this function to
    if ( key( $usermeta ) === 'user_role_name_goes_here' ) {
        // Check for order status i.e. cancelled, failed, on-hold, pending, processing, completed
        if( 'processing'== $order->get_status() ) {
            // Change order status i.e. cancelled, failed, on-hold, pending, processing, completed
            $order->update_status( 'completed' ); 
        }
    }
}

add_action( 'woocommerce_thankyou', 'user_role_order_status', 10, 1 );

?>