adl_fcmSendData returns ADL_RET_ERR_UNKNOWN_HDL in UART 2


I’m trying to use the UART2 for normal serial communication using FCM and here are the steps i follow.

i first subscribe to the FCM service in UART2 using ,
adl_fcmSubscribe (ADL_FCM_FLOW_V24_UART2, (adl_fcmCtrlHdlr_f)cntrl_handler, (adl_fcmDataHdlr_f)data_handler );

Then in the ADL_FCM_EVENT_FLOW_OPENNED event, i switch the mode to data mode using,
adl_fcmSwitchV24State ( FCM_Handler, ADL_FCM_V24_STATE_DATA ); ,which also returns OK.

now when i try to send some data on the UART2 using adl_fcmSendData it returns an error saying,

Can anyone please tell me why this is happening as i believe if the switch state returns OK for the same handle, there is no reason for the adl_fcmSendData to return with an Unknown Handle Error.

Thank you,