iOS Parse Facebook Login error 308 FBSDKLoginBadChallengeString -

i'm trying implement facebook login in ios app, using parse.

let permissionsarray = ["public_profile", "email"]  pffacebookutils.logininbackgroundwithreadpermissions(permissionsarray)     { (user: pfuser?, error: nserror?) in      if let user = user {         //we logged in!     }     else {         //login error!     } } 

this works in simulator, not on device. on device, error:

error domain=com.facebook.sdk.login code=308 "the operation couldn’t completed. (com.facebook.sdk.login error 308.)

error code 308 fbsdkloginbadchallengestring, "the login response missing valid challenge string."

after authorise app on facebook, gets called:

func application(application: uiapplication, openurl url: nsurl, sourceapplication: string?, annotation: anyobject?) -> bool {     return fbsdkapplicationdelegate.sharedinstance().application(application, openurl: url, sourceapplication: sourceapplication, annotation: annotation) } 

the url is:

fb1640722449492705://authorize/#state=%7b%22challenge%22%3a%225okwv3wn%2beh%2bequ48xv6ty%2bruek%3d%22%2c%22com.facebook.sdk_client_state%22%3atrue%2c%223_method%22%3a1%2c%220_auth_logger_id%22%3a%22564cd915-2cfc-4989-9af6-cea389908d51%22%7d&granted_scopes=user_birthday%2cpublic_profile&denied_scopes=&signed_request=c8sbbdeanpf-r_xtyx4lra0bwm5p9iwxdr8m4nl3yxi.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&access_token=caaxuonbg6uebantad9dzwbsu4lloecpsu86ny0ir

yes, followed in parse's facebook login guide (made sure bundle ids match, implemented required appdelegate methods, etc).

what error mean , how solve it?

a simple solution work me. enable keychain sharing in capabilities