Amazon have initiated a voluntary recall related to Fire 7” and UK Fire Kids Edition 7” tablets sold in the UK since September 2015. When the supplied power adapter is pulled from the wall socket, 'the adapter assembly may detach and create a risk of electrical shock'. It's probably worth doing then!
Detailed on this page on the Amazon UK website, the company confirms they are offering to replace these power adapters with a new adapter free of charge, or alternatively apply a £12 account credit to allow customers to purchase their own replacement. Much better - after all, you could pick yourself up a nice Qualcomm QuickCharge 3 compatible charger for under £12, that would work great with your phone too. :)
Customers should stop using the existing adapter immediately and a replacement adapter is received, they can use the included USB cable connected to a computer or another compatible adapter to charge the tablet.
Are you affected? Check your adapter for the code 'FABK7B', as shown below, to find out.