BLE_DB_DISCOVERY_ERROR in SDK13, s132, nRF52, central role

[Mikhail]

I use example from SDK 13 ble_app_uart_c. I changed uuid to my uuid from nrf51 peripherial device. I get event BLE_GAP_EVT_CONNECTED where made

err_code = ble_db_discovery_start(&m_ble_db_discovery, p_ble_evt->evt.gap_evt.conn_handle);

after that I didn't receive

case BLE_NUS_C_EVT_DISCOVERY_COMPLETE:

but receive BLE_DB_DISCOVERY_ERROR.

Screen attached. Why it happens?