Error trying to save update object to database - iOS/Swift

Backedless 4.0.15
I’m trying to save my updated order object to the database and get the following error:

2017-10-14 19:22:29.263144 Yeti[876:180255] *** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<NSConcreteValue 0x174e457f0> valueForUndefinedKey:]: this class is not key value coding-compliant for the key objCType.'

I’m using the same function to both create and update the object as described in the documentation:
"Updating a data object which has been previously stored in the Backendless data store can be done using the same API as for saving the object initially. "
When I use the function to create the object it works fine, when I try to update it I get the error. This is my create/update order function:

func createOrder(_ order: Order, completion: @escaping (Order?,Fault?) -> Void) 
 print("Begin create order service")
 let dataStore = backendless?.data.of(Order.ofClass())
 response: { (result: Any?) -> Void in
 print("Create order response received")
 let savedOrder = result as! Order
 print("Order saved: \(savedOrder.userId)")
 let user = self.backendless?.userService.currentUser
 self.setUserOrderRelation(order: savedOrder, user: user!)
 result, error in
 if let result = result
 completion (savedOrder, nil)
 else if let error = error
 completion (nil, error)
 error: { (error: Fault?) -> Void in
 print("server reported error: \(error)")
 completion(nil, error)

The error comes up as soon as is executed.
App ID: B8F9484B-C42E-80FB-FFA6-B6DAC0B90900

Got this working, no need to investigate.

Tried a lot of different things so not sure exaclty what the issue was but I was updating my order data model and looks like I had some sync issues between my old and new data models.