There are couple things you can do as a Sphere Administrator:

1. Run the Payment Detail Report
*Control > Reports > Billing Payment Detail Report
*Change then Date Range when needed
See if the transaction is there.

2. Run the Activity Summary Report
*Control > Reports > People > Activity Summary Report
*Click Customize button to change the date range.
Note: By default, the report pull result from the last full month
*Run Report > Click Drill down next to 'Failed Transaction'
See if the transaction is there.