Paying for a subscription for a phone I don’t have

I sold me old iPhone about 3 months ago and noticed again a £2.99 iCloud storage charge come out again which is for that phone. I have tried the steps of getting an email verification code as I can’t access that phone or number but do have the backup email address, I waited about 15 minutes and pressed re-send code but nothing ace through junk or any inbox and it is 100% the right email address Apple have. I tried then the option to give you my new number and after a few days you will be able to confirm my identity using that one but it kept saying it’s not a valid number! It is it’s the one that came up automatically on predictive text which is my number and I also tried typing it in with and without the country area code and also with just a 0 and without any area code or 0 at the beginning. It says I’ve tried too any times now. I don’t have the credit card I used to set up that payment and it shows on my bank statement that it’s a payment taken via PayPal which is why Apple are able to take it even though I no longer have that card.

it feels a joke that I haven’t had any verification email and it doesn’t think my number is correct and is using an invalid card. Considering it’s something most people do at some point (sell an iPhone - which i did restore back to factory settings beforehand) it feels like it’s their way of getting extra payments for millions to make billions as it’s so difficult and none of their simple and normal steps work.

what can I do? I need to cancel this payment.