Can I place multiple orders for the same link at once?
You can absolutely place multiple orders for the same post or link at the same time if you're ordering two different services, such as likes and comments.
If you try to place two orders for likes on the same post before the prior order is marked as complete, you will receive an alert asking whether you want to proceed or wait (recommended). This is due to the fact that only one order per service and post/link can be completed at any given time.
If you opt to proceed regardless, the latest order you just placed may experience more delays than if you had waited for the other order to complete first. Regardless, it will complete.