If you are seeing a message that you've already collected bonus coins from, say, an email offer or from our Facebook App Page, the issue could be the result of having attempted to collect the bonus coins, our server recognizing the fact, and a brief interruption in that communication back to you. Therefore, you wouldn't be aware that the coins had been awarded and you would naturally try again only to see the message that you've already done so.
That's one possibility; there could be other scenarios contributing to the issue.
Whatever the reason, our Support Team is happy to help! Just send us a request using the link to the right of this article and we'll be happy to assist you.