I'm going to be setting up a ltd business with a business bank account, just not sure whether I need to be VAT registered?

I want to test SKPaymentQueue.default().restoreCompletedTransactions() for a non-consumable in-app purchase. But when I delete the app in simulator, and reinstall (i.e. recompile it), all the transaction data in Xcode > Debug > Storekit gets deleted/cleared out, so how am I supposed to test restoring data for the scenario of when a user deletes and reinstalls the app?

I'm trying to set up my banking, but I'm getting the error message "The bank identification code you selected does not match the corresponding part of your IBAN." All my details are correct. However, my bank seems to use a different provider for its IBANs, which is where the verification is failing. I'm a bit confused to what Apple actually pay into - the bank account/sort code combo, or directly into the IBAN? If it's the former, why do they even ask for the IBAN and verify against it? Has anyone experienced this, and how did they resolve it? Apple support sent me a link where people were using the IBAN breakdown to reverse-engineer an account number/sort code from it, but when I mentioned this to my bank, they told me to not do this. Thanks in advance