@Justine284
Hi Justine, two things would have happened.
When you changed your email address you would have received an sms to your phone with a link to tap to verify that the change of email address was genuine.
The other thing that would have happened when you changed your payout account details you would have within 30 minutes got an email that looks like this.......

Can you verify to us that both those things did happen?
If you didn't respond to the payout email within 72 hours Airbnb would have sent a few cents to your new account as they would assume that the details of the change are correct.
Justine click your profile photo top right corner of the screen, >to your Account > Payments & Payouts > Payout Preferences and you will be faced with a screen similar to this.......

It can take up to 7 days for changes to come into effect. We here in Australia are on a delay compared to the US.....those carrier pigeons have a long way to fly.....

If everything checks out either email Trust and Safety at https://www.airbnb.co.uk/trust
or call the Sydney number 02 85203333 and get an agent to check it out.
All the best.....
Cheers........Rob
Edit:....As an aside Justine, I have a poster that was produced for a Burt Bacharach/Carole Bayer Sager concert tour in the early 2000's when they were to give a concert at the Crackenback resort sound shell. The poster is the best I have ever seen!
All it is , is a washed out face image of Burt Bacharach and simply scrolled across the front of it in bold script is....
"Bacharach at Crackenback"!