I'm an undergraduate college student and I was recently promoted to supervise 20 employees (all of whom are also college students around my age) at a 24-hour residence hall desk. I've been part of this sub for a while and I strongly believe and agree with treating employees with respect, dignity, and as human beings. But I'm struggling with the power dynamic. As soon as I got promoted, the people who used to be my coworkers started regularly calling in sick, blantantly not showing up to their shifts, and stopped doing what they were supposed to be doing at the desk (i.e. calling residents about borrowed keys, keeping track of important documentation, and completing audits). We literally lost a number of expensive keys and cards that could give strangers access to buildings and/or apartments. I spoke to my own supervisor about it, and he told me to start writing people up (which, now that he knew about it, he was going to hold me accountable for following through). I've now written people up for missing meetings or shifts without notice, not finding coverage for their shifts and not showing up, I've had zoom meetings to talk about why what they were doing was not ok, and I can't help but feel like I'm an absolute asshole. Obviously, some of my staff are not happy with me (a good number of staff have been understanding and are upset with how their coworkers are fucking them over). I keep thinking that there have to be underlying circumstances and that people aren't being dicks on purpose. I mean I get that college is stressful, but there's been no communication on their end, and they signed a contract knowing the responsibilities of the job. Is there anything that I could be doing better? Any tips?
Edit: I'm sorry if any of this comes off as harsh. I'm just extremely stressed as a college student myself balancing work and school on top of this.