Leave of absence (loa). It is not leave of package absence. That doesn't exist. Leave of absence does. I've worked for several companies and it's not leave of package. This business language doesn't exist in office language. It's leave of absence.

Loa is any time off request going beyond 30 days off. If it's less than that you'll need to use your sick pay and vacation pay up first. Per their rules. If you are taking medical leave of absence they might let you use sick pay up. Might. There is no phone number to leave a loa letter or request. You write a small professional loa letter and turn it into your store manager. Save a copy for your self. This info is in your union handbook under leave of absence request. It's not guaranteed it will be accepted but it's worth a try. Not much gets rejected. It does help if you have a valid dr's note for medical leave. They're not hard to get. If taking medical loa all you need say is medical. Hippa protects the rest.

Keep letter simple and to the point. Any worriedness could hinder the request getting accepted. Need help writing it? Google examples on leave of absence letters. Copy paste into word and replace their examples with what you need. As a side note you will not get paid for loa requests. I hope you have some funds set aside or can live off of someone else's income.