ServiceLedger is going to prevent you from performing an operation that will create orphan accounts and/or undermine the integrity of your database. In instances where you are trying to delete a record or transaction and receive a "Delete Statement conflicted with Reference constraint 'x" (where X references the table of reference)" error, ServiceLedger is preventing you from performing an operation that potentially can create an orphan record and/or undermine the integrity of your database. This error is not a bug or anamoly and is considered a catch-all error to catch (and prevent) any operation that could create future database issues.
The referencing table that follows is generally a good clue of where the reference culprit lies and what needs to be resolved, if possible, before you can continue with the delete operation. In some instances, it may be necessary to go several levels deep on transactions before a transaction can be deleted.
In general, it is recommended that you close and re-open ServiceLedger after you receive the error to clean out any residual effects of the error from the current session. Afterwards, it is recommended that you review the record or transaction in question and try to determine any references or links to that record or transaction and delete those references or links first. In most instances, the referencing table will provide some clue of the type of reference or link you should be looking for.
If you require any direct assistance, email the error you are receiving to email@example.com and they can assist you with further documentation on the specific reference constraint error you are having.