remove ‘option’ from here
this
$canb_name = get_sub_field('canb_notification_bar_name','option');
should be
$canb_name = get_sub_field('canb_notification_bar_name');
I’m not sure that is causing your error, but that’s the only thing I can see wrong. For some reason your code is causing an infinite loop.
Also, you should be using the acf/prepare_field hook to modify the field message. While acf/load_field can be used here it can have unintended side effects.