It was possible to pay for Spotify Premium using Apple’s in-app payment system (iAP). However, this has been discontinued for new subscribers. There's more info about this in this support site article.
If you currently pay for Premium with Apple’s in-app payment system, we'd recommend first making sure to cancelthe automatic renewal of your Spotify payment with Apple to avoid further charges.
We'd also suggest checking our refund policy here for more details regarding one.
Let us know how you get on! We'll be happy to lend a hand if there's anything else we can help with.
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