Zelle never states that a payment can be reversed under no circumstances. The cited User Service Agreement (paragraph 11) basically relieves Zelle and Bank of any liability from the payment. In other words, they don't have the responsibility to reverse payments in a fraud situation.

Zelle Customer Service
Zelle is a popular money-transfer app that sends cash almost instantly. You can send a payment by entering the recipient's email address or phone number. Zelle is a money transfer service that makes payments easy.
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