Thank you for reaching out to the Community. We moved your post from Chats to the help boards as its content fits better here.
Keep in mind that the official language used in the Community is English; the replies will be posted in this language. We appreciate your understanding.
As Spotify billing works as a prepaid service, every payment you make gives you 30 days of Premium active in your account (excluding Premium mini). When you update the payment details, the Premium you already have doesn't get removed from the account, but it could generate a small charge to verify if the new card is active. This is a bank process and is called "Verification charge".
However, if you updated the payment details, but in a different account by mistake, the system will generate a second subscription for the other account.
Since we don't have access to users accounts from the Community, to check what happened with the payment and to avoid a secondary subscription, we'd recommend contacting our Customer Support, so they can check your account and help you further.
Hope this helps. If anything else comes up, the Community will be here for you.
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