Try aceseccing through your amazon account if registered to you that might workFiretv app only works if already paired up
Only other thing I can think of is going on amazon see if you can activate firestick that way if you have an amazon account or seeing if you can get a replacement remoteNo amazon account for this, as second hand, app does not work, would any other remote work?.
thanks in advance
Just looked on amazon £14.99 for replacement remote for firestickTry aceseccing through your amazon account if registered to you that might work