Sub-tree contains contra item -> deletion not possible

What causes this issue?

The sub-tree on which the cursor is, is to be deleted but contains a
contra item. Contra items cannot be deleted.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

First delete the contra item with "Edit -> Delete contra item".
Afterwards you can delete the sub-tree which contains the contra item.

Error message extract from SAP system. Copyright SAP SE.