I got charged twice for premium but my account said it's still a free account
Hi @RuangNegatif, welcome to the Spotify community!
When we subscribe to Premium, Spotify sends us an e-mail with the purchase receipt. It contains the information about it, including usermane.
Please double check if you're logging in with the correct credentials.
Besides, you can check here if you have more than one account (and logging in the wrong one).
Let me know if this helps!