When you received two payments by Spotify at the same day, and this has never happened before, there are two possible reasons.
The first one is that one of the charges is a pre-authorization charge. Normally the pre-auth charge has a smaller amount of money and it should be away after a few business days.
If this isn't a pre-auth charge, then it’s possible that you hit the conformation button in the subscription email twice and so a second transaction went through. Don't worry, this second charge will just get added onto your account as if you "pre-paid" for an extra month. You can see this by visiting your subscription page and checking that your new payment time will be in around 2 months.
Have a nice day!
Help others find this answer and click "Accept as Solution".
If you appreciate my answer, maybe give me a Like.
Note: I'm not a Spotify employee.