Looking for career advice - where to go from here?

Hi all, I'm stuck in a rut and I'm hoping for some advice.

I'm 38 years old, based in the UK, and I'm currently in a dead-end job as a copy editor on a £40k salary. I previously worked at a B2B agency as a copywriter for 3 years (I've now been in my current role for 4), and while there were more opportunities to be creative, the pay was worse (28k), and the commute wasn't great, whereas I now work from home.

I want to move into a more creative role - because I'm currently just a human spell-checker - but can't afford to take a pay cut, and I haven't had anything to add to my portfolio since I started.

What's the best way out of this?

Thanks in advance!