Link to previous discussion for my own reference later
This is an odd error to get. It means that you are calling Delete() on a document that does not exist in the local database (Or somehow you’ve called delete on a document with a null revision ID). Or at least the reference you have thinks that it doesn’t exist (if you are using multiple databases on multiple threads on the same file they will not all be consistent with each other all the time).
Do you have a certain method that you can provide for reproducing this issue?