This is happening to me too and I don't know what to do. I got a notification from Spotify saying I need to update my payment details for premium and when I selected indervidual it said that it wasn't available for my account t and was trying to make me pay for duo.
If you get the prompt to upgrade to a Duo subscription when you're trying to update the payment details, the way to update the payment details is to cancel the current subscription and activate a new Premium Individual subscription with the new payment method. Could you afterwards confirm, that this has resolved the issue?
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