Working capital is a critical part of any business, it can be defined as follows; the capital of a business which is used in its day-to-day trading operations, calculated as the current assets minus the current liabilities.
In short, today how much to you own, minus how much you owe. To be solvent, you need to own more than you owe. If you owe more than you own, you need to sell some stock or unused accepts or make a loan, only if you are sure you can pay it off without making your situation worse.
GET ADVICE, this is serious!