National Insurance query

Cobbler_tone

There are strange things that go on in the system.
My mum and dad have received extra WFA each again. One year they both got £300, this time they got £300 and £150. It is clearly to do with my dad. The NI number and name are correct, the letter says his is reduced due to time in a care home. Neither of them have been anywhere and must be mistaken identity somewhere, or someone with fat fingers. He mentioned it as thought they should be getting £300 each, until I said it was per household. 
It will probably get unravelled at some point and recovered.

Could well be an error.