Board Thread:Questions and Answers/@comment-25262775-20140804030456/@comment-3241231-20140805023427

It looks like the Bind Account option was removed fairly recently, with no reason given. As far as I know, there's no other way to bind accounts unless you set up a universal account on your old phone.

The other option would be to send a ticket through the iPhone app explaining your problem, and hopefully giving the developers some information about your former account.

The losses mentioned in that forum thread were when iOS accounts were transferred to facebook accounts - those transfers aren't being performed any more, and any account binding doesn't have those issues.