Is The Landlord or Tenant Responsible For This?

Hey everyone, I haven't posted about it but I closed on my first duplex in February & now I am so happy I can finally call myself a rental property investor.

But sure enough Into my first month I learned this one tenant loves to text and call to request a bunch of minor fixes that seem to be something that I'm not sure if I should be responsible to fix or if the tenant should fix it.

Like this photo I got a text about this falling down in the middle of the night but clearly I can see that its too much weight being put on the bar. I already texted her to clean the space out and I will have someone put it back up.

But I wanted to know what is some of the things in a unit the tenant should be responsible for?