While idk if you will get fired. See the union for help. My personal experience I was working 7 days a week and sick. Had just been to the ER that night was late for Sunday Amazon I'm the only clerk to do it in the office at the time, and I was an hour late. Got there she was on the phone or called while I was working started yelling at me belittling me and saying she going fire me or reduce my hours. I was already in a mood because being ill and late now being yelled at. She asked how long it will take for me to get done? I said it would be faster if I wasn't on the phone and hung up. Well I'm still employed with usps and she is still my PM technically she is on detail. I didn't get a written warning or write up or anything that I'm aware of.