@projectSB see if this helps, I've added below code when I got a similar error

def on_data(wsapp, message):
        if message != b'\x00':
            #process data

@admin123 @admin Unable to fetch historical data beyond 10th Oct. It was working recently.
Below is the error message.

@projectSB see if this helps, I've added below code when I got a similar error

def on_data(wsapp, message):
        if message != b'\x00':
            #process data

@admin How can I get expired NFO contract's token number so that I can can fetch historical data for expired contracts?