Open the project and locate the rule, then select the rule and click Delete, then click Delete to confirm. You will be asked to confirm if you want to delete the rebate. This action cannot be reversed. You can only delete one rebate at a time.
If a rebate has posted transactions, you won't be able to delete it. However, you can set it as 'inactive', which means it won't be included in calculations.
Deleting a parent rebate also deletes all associated child rebates. If you delete a parent rebate you will get a warning. If you proceed, the deletion can not be undone.