In an early stage of the Direct Debit integration the merchant will have the possibility to test the product in a test environment called 'Sandbox'.
In this environment, when starting the mandate subscription flow, it will be possible to subscribe through a test bank, which will sign a fictitious mandate. Subsequently, the merchant will be able to request collections from users whose rout has an active mandate created from the test bank. All these charges will be fictitious and no real money transfers will be made.
In order to simulate the unsubscription of users and the rejection of collection settlements by the bank due to insufficient funds, probabilities have been set up for these events. Thus, every day each fictitious mandate has a 1% probability of being unsubscribed and each collection has a 3% probability of being rejected due to insufficient funds.