Once there is no need for there to be a payment arrangement for a tenancy, it can be deleted from their record. 

From the Tenancy Record, click on the 'Payment Arrangements' button at the top of the screen:

To remove the Payment Arrangement, simply delete all of the information from the Transaction Type, Amount, Start Date and Comments fields. It should go from the example below:

To this: 

Make sure that you leave a value in the amount field.