Sync gateway dont return a document with param open_revs=all

[Eduardo Camargo]

i have this architecture
couchbase server 4.5.1
couchbase lite 1.3.1
sync gateway 1.3.1
node js v6.11.0

I am resolved conflicts in side server with node js script , the  script resolved many conflicts but in specific document in part where request open_revs all of document (for select winer rev) my script in node js take many minutes.

i took URL and throw request whith other program (POSTMAN) 
Syntax: http://localhost:4985/shadow_bucket_name/IDdocument?open_revs=all

but the sync gateway don't respond me a document
I waited approximately 30 min and nothing, with others documents average of response time its less than 300 ms.

i search the document in console of couchbase in shadowBucket but I don't see the body of this because throw this warning

Warning: Editing of document with size more than 256 KiB is not allowed

in my normal bucket the document only have 13 lines of body don't make sense
i suppose that the document its large because i have many conflicts and many revisions

but my problem its why don't return a document

thanks for replys