VersionedModel.findOne stops execution

[vladexologija]

For some reason when I add mongoose-version as plugin my model save blocks.
When I imported the library into the project and added breakpoints managed
to pinpoint this to the line https://github.com/saintedlama/mongoose-version/blob/master/lib/strategies/array.js#L72.
Find one is called with params { refId: 538c63e5d866b72e36959c18 } and
there it stops.
Do you have any idea why is this happening?
Thanks for any help!