You will sometimes notice Creators will send you content in Direct Messages that are locked.
It can be unlocked for a price and all you need to do is click on the Unlock button:
Then you will need to confirm the purchase:
Once unlocked you will see the purple notification in the chat. If you click on the notification it will lead you straight to the unlocked DM!
Note that all the content you receive/unlock in chats can be accessed in the same chat with the creator or in your Purchases tab.