You can choose the packages of likes for the same post as many times as you want. You can start with a hundred likes and then choose several hundred and subsequently a few thousand. You have the liberty to get as many likes for one or several posts to get the desired exposure. However, you should have one campaign for a particular post end before you begin another. If you choose five hundred likes for a post, let them be delivered and then choose another package for the same post if you want. Simultaneous campaigns for the same post are unnecessary.