AWOL or employees who are Absent Without Leave is a conduct issue and should be dealt with following your Company’s disciplinary procedure.
AWOL issues often arise when an employee does not arrive as expected for work and remains out of contact from their line manager. This can occur when holiday has been refused but still take by the employee, when the employee has failed to return after planned holiday or in some instances where a GP’s fit note has expired and the employee has not remained in contact with the Company and has not provided a further GP’s fit note to sanction their period of sick absence.
In all of these issues you would need to investigate the period of absence and ascertain whether it is deemed necessary to follow up with disciplinary action. It is always the employees responsibility to ensure that the report any period of absence to their line manager, be it sick absence of holiday.