Service-less Postnet in Secunda

I went to Postnet to fetch my delivery and found them closed. I arrived at 17h00 and they have it written that they close at 17h30. I called the "emergency" number written on their window. The phone was off and I left a message. No one contacted me since.

I understand there was a power outage in Secunda but if that was the reason, why couldn't they put up a notice ?