# Fraud Scenarios

Fraud Scenarios to always look out for:

1. If you see a `transactionId` being reused and/or an incorrect verifier, the callback URL is not coming from the ArcPlay.ai and should be considered as fraudulent.
2. If your `userId` or `clientId` contains only the integers we recommend to perform a simple validation to make sure the `userId` or `clientId` isn’t being manipulated. For example, ArcPlay.ai considers `001234` and `1234` two separate unique Ids while your backend server logic may not.
