V3-2 chapter 20 error

When trying to run starter project I receive the following error:TideWatch[17255:1037278] *** Terminating app due to uncaught exception ‘NSInvalidUnarchiveOperationException’, reason: ‘*** -[NSKeyedUnarchiver decodeObjectForKey:]: cannot decode object of class (TideWatch.TideConditions) for key (root); the class may be defined in source code or a library that is not linked’
Any suggestions?

@jack_wu Can you please help with this when you get a chance? Thank you - much appreciated! :]