Hi fiona268,
I understand that you are trying to change your iTunes Store country, but you can't because of your iTunes Match subscription. I know it's important to have access to localized content, so I'm happy to provide some help for this.
Check out what this article has to say about this:
If you can’t change your iTunes Store country or region - Apple Support
If you subscribe to iTunes Match or have an Apple Music membership, you need to wait for your iTunes Match subscription or Apple Music membership to expire.
You might also need to cancel automatic renewal for iTunes Match or turn off your automatically renewing Apple Music membership.
After your subscription or membership expires, you can change your country.
Once you cancel the subscription, it is still active until the end of that billing cycle. Once that billing cycle is over and iTunes Match is no longer active, you can follow the steps here to change your iTunes Store country:
Change your iTunes Store country or region - Apple Support
Thanks for using the Apple Support Communities, cheers!