MITM Bond Failure Android 5.0 and nrf51822

Question

I am working on a custom service using and nrf51822 device. SDK7.1 SD7.1

My security parameters are as follows:

#define SEC_PARAM_TIMEOUT 30 /**< Timeout for Pairing Request or Security Request (in seconds). */
#define SEC_PARAM_BOND 1 /**< Perform bonding. */
#define SEC_PARAM_MITM 1 /**< Man In The Middle protection required. */
#define SEC_PARAM_IO_CAPABILITIES BLE_GAP_IO_CAPS_DISPLAY_ONLY /**< No I/O capabilities. */
#define SEC_PARAM_OOB 0 /**< Out Of Band data not available. */
#define SEC_PARAM_MIN_KEY_SIZE 7 /**< Minimum encryption key size. */
#define SEC_PARAM_MAX_KEY_SIZE 16 /**< Maximum encryption key size. */
 
 My initialization is as follows: 
 void device_manager_init(void)
{
uint32_t err_code;
dm_init_param_t init_data;
dm_application_param_t register_param; 
 // Initialize persistent storage module.
err_code = pstorage_init();
APP_ERROR_CHECK(err_code);

err_code = dm_init(&init_data);
APP_ERROR_CHECK(err_code);

memset(&register_param.sec_param, 0, sizeof(ble_gap_sec_params_t));

register_param.sec_param.timeout = SEC_PARAM_TIMEOUT;
register_param.sec_param.bond = SEC_PARAM_BOND;
register_param.sec_param.mitm = SEC_PARAM_MITM;
register_param.sec_param.io_caps = SEC_PARAM_IO_CAPABILITIES;
register_param.sec_param.oob = SEC_PARAM_OOB;
register_param.sec_param.min_key_size = SEC_PARAM_MIN_KEY_SIZE;
register_param.sec_param.max_key_size = SEC_PARAM_MAX_KEY_SIZE;
register_param.evt_handler = device_manager_evt_handler;
register_param.service_type = DM_PROTOCOL_CNTXT_GATT_SRVR_ID;

err_code = dm_register(&m_app_handle, &register_param);
APP_ERROR_CHECK(err_code);
 
 } 
 While using the windows x64 MCP I request a bond and a dialog box pops up and I type in the corresponding passkey. The bond is successfully made and all characteristics are able to be accessed. 
 However, while using android when I request a bond no dialog box shows up. My assumption is that android thinks a "just works" bond needs to be performed. The results is an insufficient bond. As a result I am unable to access characteristics requiring MITM security.

MITM Bond Failure Android 5.0 and nrf51822

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