Subscriptions made through the App Store or Google Play Store are billed in US dollars (USD). This can cause confusion if your local currency isn't the same.
When you receive your credit card bill, the USD amount is converted to your local currency.
Higher values may also mean that you made a longer subscription plan, such as half-yearly or yearly. In this case, you should check which subscription plan is active.
To check your subscription plan for Apple devices, click here and follow the instructions.
To check your subscription plan for Android devices, click here and follow the instructions.