My cat has started pooing in corners!

[WentworthMillerMad]

Can anyone help? I have 2 cats, they v happy and nothing has changed.

From no where one cat has started pooing in the same corner every day.
I thought it may be te weather so have put a tray down but no use.
I have just cleaned up again, window open blah blah.

Any ideas? Thanks

Would tea tree oil put cat off the corner?

or orange peel? Once they have started doing it, the lingering smell tells them 'this is a place to poo'

Orange peel I can do! Thanks