Isabella Oliver discount link doesn't appear to be working - has it expired?

[Bex78]

I have used the mumsnet Isabella Oliver discount link on and off for about 3 years, but when I tried to use it this week, the 10% discount didn't apply itself automatically when I clicked through to Checkout. Is the discount no longer valid? Has anyone else had this problem? Does anyone have an IO discount code they could share? Thanks!!