ble_nus_string_send error

[ps_anu]

hi........... folks

i am merging two programs together uart and TWI sensor ...using nrf52382 and segger 15.2version

i am getting the error in ble_nus_send ,

even i have enabled BLE_NUS_ENABLED  ..and all the c files including ble_nus.c files    still getting the errors

 thiese are errors

Output/ble_app_uart_pca10056_s140 Release/Obj/main.o: In function `nus_data_handler':

undefined reference to `ble_nus_string_send'