ios - Data from API call and jsonobject is not carrying over when called -

i'm calling api , it's jsonobject in segue, , trying push view controller, it's not carrying data. in below code prints fine in call, other 2 prints come null.

is there i'm missing make data persistent?

- (void)prepareforsegue:(uistoryboardsegue *)segue sender:(id)sender { if ([segue.identifier isequaltostring:@"showchangedetail"]) {     nsindexpath *indexpath = nil;     bnritem *item = nil;     //bditemchangedetailapi *itemapi = nil;     nsarray *items = [[bnritemstore sharedstore] allitems];      if (self.searchdisplaycontroller.active) {         indexpath = [self.searchdisplaycontroller.searchresultstableview indexpathforselectedrow];         item = [searchresults objectatindex:indexpath.row];     } else {         indexpath = [self.tableview indexpathforselectedrow];         //item = items[indexpath.row];         item = [items objectatindex:indexpath.row];      }      nslog(@"111111%@", self.apiitem);     [self fetchfeedapichangedetail];       nslog(@"222222%@", self.apiitem);     bdchangeapprovecontroller *destviewcontroller = segue.destinationviewcontroller;     destviewcontroller.itemapi = self.apiitem;   } }  - (void)fetchfeedapichangedetail { //nsstring *changeorder = changeorder;  // nsstring *requeststring = [@"http://url.com];  nsstring *requeststring = @"http://url.com";  nsurl *url = [nsurl urlwithstring:requeststring]; nsurlrequest *req = [nsurlrequest requestwithurl:url];  nsurlsessiondatatask *datatask = [self.session datataskwithrequest:req                 completionhandler:  ^(nsdata *data, nsurlresponse *response, nserror *error){       nsdictionary *jsonobject1 = [nsjsonserialization jsonobjectwithdata:data                                                                 options:0                                                                   error:nil];      //nslog(@"%@", jsonobject1);      self.apiitem = jsonobject1[@"codetail"];      nslog(@"%@", self.apiitem);  }];  [datatask resume];  }  - (void) tableview:(uitableview *)tableview didselectrowatindexpath:(nsindexpath *)indexpath { // show loading indicator __weak typeof(self) weakself = self; [[bnritemstore sharedstore] fetchfeedapichangedetail:^(nsarray *array, nserror *err)  {      [weakself performseguewithidentifier:@"showchangedetail" sender:weakself];      // hide loading indicator  }]; }