Step 1:
In the upper-right corner, click on "Balance."
Step 2:
Within the drop-down, click on "Payment Settings"
Step 3:
Click on "Add card."
Step 4:
Fill in the card information, choose to make this the default card, and click "Add card."
How do I add funds / change card on file?
How to add additional funds to get you through until the new billing cycle begins.
Written by Support and Success at Mobiniti