I test ancs when connect second iphone Will appear p_file_name: 0x20001c08 "src \ gap_core.c" ，This is what causes？

Question

Hi all, 
 I use nRF51822, nrf51_sdk_v5_2_0_39364 and s110_nrf51822_6.0.0.Test ANCS, first with the iPhone connection is no problem. When I disconnect, connect a second iphone, will appear this error error_code: 0xDEADBEEF, line_num:0x000005c1,p_file_name: 0x20001c08 "src \ gap_core.c" I do not know why.? I use ble_bondmngr_cfg.h code: 
 /**@brief Number of CCCDs used in the Apple Notification Center Client application. */

 #define BLE_BONDMNGR_CCCD_COUNT 5

 /**@brief Maximum number of bonded masters. */

 #define BLE_BONDMNGR_MAX_BONDED_CENTRALS 2

main.c code：

1470 line switch (p_ble_evt->header.evt_id)

1471 line {

1472 line case BLE_GAP_EVT_CONNECTED:

1473 line 
 
1474 line // err_code = app_button_enable();

1475 line // APP_ERROR_CHECK(err_code); 

1476	line 

1477 line m_advertising_mode = BLE_NO_ADVERTISING;

1478 line m_conn_handle = p_ble_evt->evt.gap_evt.conn_handle;

1479	line 
 
1480	line display_wcfalg=1;

1481	line err_code = app_timer_start(m_firstcon_timer_id, FIRSTCON_INTERVAL, NULL);

1482	line 
 
1483 line APP_ERROR_CHECK(err_code);

1484 line break;

1485 line case BLE_GAP_EVT_CONN_PARAM_UPDATE:

1486 line case BLE_GAP_EVT_AUTH_STATUS:

1487 line apple_notification_setup();

1488 line break;
 
 Hope to get your help！ 
 Edit: FORMAT