PMAlertController | customizable alert that can substitute UIAlertController | iOS library

I am developing an app where you can add items to a Table View using the Realm Database. At the moment, I can add an Item to the Table View but it's being added twice to the Realm Database. This then means that if I shut my app & then go back into it, the new Item I had previously added appears twice, once in the new position & once replacing the item which was in the table view just above it. Attached is my code. I've tried various different things but just can't figure out how to fix it. Thank you for your help!

This is the code where I am adding the item to my Table View/Realm Database:

This alert controller is initialized:

I have an error that occurs when I add or delete data from a node in firebase. When the data is added or deleted on firebase I get an array index out of bounds error. My array has two items, but the tableView thinks that there are three items and thus tries to access a value that doesn't exist. I can't figure out how to prevent this. For more context I am using an alertView with a closure that performs the adding or deleting of information in firebase. This alertView is in the didSelectCellAtIndexPath method. The error is occurring in the cellForRowAtIndexPath Method when accessing the array like so user.id = self.bookRequestors[indexPath.row]

Here is some of the code I wrote: `