Question about Notification

Hi Dialog
I see sample code use the below function to send a notification to a peer device:
void prf_server_send_event(prf_env_struct *p_env, bool indication, uint16_t handle);

Now,the length of characteris value is 19 Bytes in my profile.
But sometimes I hope to send a notification with the value length is changeable but not always 19 Bytes.
What should I do?