Batch Update request puts NSNumber fields to nil [Swift] - ios

Question

I'm working with web app. I have UITableViewController which deals with NSFetchedResultsController. I store tableView's objects through CoreData. When a user refreshes UI I perform server request and then call batch update for each new entity, my CoreData class looks like:
extension DBOrder {
#NSManaged var comment: String
#NSManaged var date: NSNumber
#NSManaged var id: NSNumber
#NSManaged var maturity_date: NSNumber
#NSManaged var number_of_tasks: NSNumber
#NSManaged var price: NSNumber
#NSManaged var status: String
#NSManaged var subject: String
#NSManaged var taskImages: [String]
#NSManaged var theme: String
}
"id" is unique for each object. "propertiesToUpdate" consists of some fields like "maturity_date": 1470427641000, "status": "some status" and etc. "entityName" is "DBOrder". And privateContext is NSManagedObjectContext type to update entities in background
func updateCoreData(id: NSNumber, entityName: String, propertiesToUpdate: [String: AnyObject], privateContext: NSManagedObjectContext) -> Bool {
let batchRequest = NSBatchUpdateRequest(entityName: entityName)
batchRequest.predicate = NSPredicate(format: "id == %#", id)
if !doesOrderExists(entityName, id: id, context: privateContext) {
return false
}
batchRequest.propertiesToUpdate = propertiesToUpdate
batchRequest.resultType = .UpdatedObjectIDsResultType
do {
let res = try privateContext.executeRequest(batchRequest) as! NSBatchUpdateResult
let orderIDs = res.result as! [NSManagedObjectID]
return (orderIDs.count != 0) ? true : false
} catch {
print(error)
}
return false
}
This function is called for each object that has been loaded from server. If object is already existed then I update it else create the new one.
Finally, the problem: when I use batch update it works incorrect with NSNumber. It always puts NSNumber fields to nil and works as it should with String fields. So, what I'm doing wrong?