Sync Gateway failed when i try to _purge deleted document

Hello everyone!
I am using Sync Gateway 2.0 and the latest Couchbase Server 5.1.

I try to purge some deleted documents so they do not replicate to my mobile device (i.e. tombstones).
I read some docs on the subject and find out that i have to use _purge REST API to get rid of such documents.
So my request is as follows /pledgedb/purge (POST) with body:
e.g.:
{ _
_ “0038072c-17d2-4424-9fd2-82d5b0c9d1f3”: [

_ “*” _
_ ]

}

I expect this document (0038072c-17d2-4424-9fd2-82d5b0c9d1f3) to be removed from database but i got following error and sync gatway failed to continue its job. I have to restart it.

I have attached my log message.

Fixed the problem by adding following lines to sg config:

“enable_shared_bucket_access”: true,
“import_docs”: “continuous”