If you would rather have your monthly charges automatically charged onto your credit card rather than receiving a monthly invoice you can add a credit card in the Admin Hub. 

Admin Hub > Settings > Billing > Add Credit Card

Then fill in all the fields and click use this card. 

To update your credit card follow the same steps as above and it will update the card that is on file to the new one. 

If you wish to remove your credit card and pay by invoice please email support@redii.com with your request.