After placing your order, it is unfortunately not possible to change its content. So did you accidentally choose the wrong product or the wrong dosage? Then contact Customer Service so they can cancel your order. You will then of course get your payment back.
Please note: is your order already at the pharmacy? Then cancellation can no longer be guaranteed. Check your order carefully before placing it!
If, for example, you only want to change your address or phone number, you can contact Customer Service so that they can adjust these details for you. Again, it depends on the status of your order whether the change can still be made or not.