What are the options when an employee leaves for the day because they were tired?? They did tell their Supervisor they were leaving, but there was a lot of work to be done. Are there grounds for immediate termination?? Would like to not offer unempl

What are the options when an employee leaves for the day because they were tired?? They did tell their Supervisor they were leaving, but there was a lot of work to be done. Are there grounds for immediate termination?? Would like to not offer unemployment for this situation. We have issued a first warning defining the issue and the consequences, but again, just wondering if immediate termination is also a way to go? Thank you.