A transactions was deleted/reversed for a Registration, Donation, etc within Sphere, but we do not know who deleted it and how it was deleted.
You can run the Payment Detail Report and display the Reversal Reason and the Reversal Description fields. If the reversal reason says Chargeback, it means that the card holder initiated the reversal through their bank or credit card company. Sometimes they forgot making the transaction and to whom. If the reversal reason says something else, then it was manually reverse by one of the sphere users.
If the transactions was deleted recently, you can access the Contact Record and go to the Record Management tab to view who last edited the transaction. If the modified date and the date of the transaction deletion do not match up, Chat with Support and reference this article.
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