LF terminator stops working when sending data

Hello,I have defined the port as following

sObject=serial('COM4','BaudRate',115200,'TimeOut',1,'Terminator','LF')

sObject.BytesAvailableFcn={@callbackSerial};

when i do fscanf in my callback function get a burst of data,even if i have a problem of buffering like you said before.

THis burst should never have happening the MOMEMT matlab saw 0A char it should have stop recieving.

Why the LF terminator stops working?

Thanks.