When an employee gives 24 hours short notice resignation, should we treat as proper resignation or treat it as abscondment?

Usually when an employee decides to resign from the company, he/she should be giving sufficient notice period (eg: weeks, months). However if an employee throws in a resignation letter and left the company the next day, does it really work out this way?

Besides if company doesn't have any policies stating 24 hours short notice resignation, how shall we treat this kinda situation?

Any HR experts/bosses mind to share your expertise on this matter?

Thanks!