Money disappearing

My accounts have woken up with money missing and with them being in a negative balance without me spending any money. Transaction history doesn’t account for any of the money being taken away. This isn’t the first time and usually the money is debited back within a day. This time it’s been close to 40 hours and no change has been made. This is an incredible inconvenience because every cent matters and there’s never an explanation as to why this happens