Possibly unhandled CastError: Cast to date failed for value "function now() { [native code] } on Mongoose
Old question but as mentioned by Ken, to create or update provide the Schema/Model with the Date value
sendHelpDate: Date.now()
This will save to the DB as "sendHelpDate" : ISODate("2018-06-27T10:49:29.328+0000"),as opposed to passing the function of Date.now see below:
message: 'Cast to Date failed for value "[Function: now]" at path "sendHelpDate"', name: 'CastError', stringValue: '"[Function: now]"', kind: 'Date', value: [Function: now], path: 'sendHelpDate', reason: [Object] _message: 'Bookings validation failed', name: 'ValidationError' }Hope the extra detail will help someone in future