My super ignores my calls

We have had many instances of the power going out in the evening and our super told us he will only respond to calls or texts outside of the hours of 9a-5p, mon-fri. I've even called the building owner about power outage issues, he says he'll call me back. Nothing. We have lost hundreds of dollars in food and medicine going bad, outside of just being annoyed/uncomfortable without power. It wasn't until I persisted with our property management that the power outages weren't our fault did they finally send an electrician, which it turns out not enough electricity was reaching our apartment. But we're still having issues. What can I do/say to get the property management to a) respond to emergencies outside of normal hours b) get reimbursed for all the food/medicine we've had to rebuy?