I purchased my subscription on the Apple Store
The entire "in app" payment system for e-Anatomy/vet-Anatomy on iOS is managed by Apple.
To be refunded, please contact Apple Support: https://support.apple.com and ask them to cancel the purchase and refund your payment.
I purchased my subscription on the Google Play Store
Please write to our technical support at contact@imaios.com and send us your payment receipt or any other proof of purchase with the transaction reference number from Google, along with your Google account email address.