When you have AWS Promotional Credits applied to your account, by default your usage will be hidden from the Cost Explorer.
AWS Cost Explorer is primarily concerned with showing you what the impact is to your billing & payments. Since Credits have already been applied to your account, you don't need to pay for it in an upcoming invoice.
Some charges for Ineligible Services not covered by AWS Promotional Credits may still show up, like Domain Registration, upfront RI costs, etc. For the rest, you'll need to change the Cost Explorer filter.
To show all usage in your AWS Account, including those covered by Credits, select the filter on the right-side of the Screen for Charge Type, change it to Exclude Only, and check the box for Credits.
Once applied, all charges on the account will be visible. Including any that may have been forgotten.
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