As Spotify is for personal/non-commercial use, we only issue payment receipts. We don't issue invoices with a VAT number.
However, we email a receipt to you at the beginning of your Premium trial, the first payment of a subscription, or when you purchase an e-card. You can also see a breakdown of the different taxes applied to your payment on that receipt.
If you haven’t received one, first make sure that you've provided the correct email address on your Account Overview page. Then, we'd suggest checking your spam/junk folder in case they were redirected there by mistake.
You can always find your receipts on your Account page here.