swift - Why do I get "JSON text did not start with array or object and option to allow fragments not set." error? -

i making request download data parse server set (in case text) , following error message

optional(error domain=nscocoaerrordomain code=3840 "json text did not start array or object , option allow fragments not set." userinfo={nsdebugdescription=json text did not start array or object , option allow fragments not set.}) 

here request code

var query1 = pfquery(classname: spotdetail)              query1.getobjectinbackgroundwithid("alkegl1d75", block: { (object, error) in                  if error != nil {                      print(error)                  } else {                     print(object?.objectforkey("name"))                  }              }) 

not whet print(aboutspot.objectid) object id

what coming from, how solve issue ?

thanks !