Apartment maintenance team is telling me it’s normal for the AC to run 10-20 degrees higher than what it’s set to.

I live in an older complex and since early July I’ve had an issue with the AC unit running 10-20 degrees higher than what I set it to. To keep my place at 75 I have to set my ac unit to 64, moving it higher just moves the temp up. I have submitted several work order since the issue began early July but the maintenance team keeps telling me it’s normal, and a few times they’ve made it worse without ever making it better. A few weeks ago I could get the place down to 70 in the night but now I’m lucky if it’s below 80. My question here is, is this in fact normal? I haven’t had an issue like this ever before and I feel like maintenance is just not doing their job here but I wanted to see if it in fact normal for older apartments