Poor attitude from Piatto manager

I’m very disappointed with service I received at Piatto Dainfern. I ordered a meal last week Friday (1st November) & they delivered spinach cooked with plastic in it. I called to complain and they collected it & I didn’t hear from them again. I called them today (Tuesday) to follow up and the manager, Basil (he refused to give me his full name) told me there was nothing to get back to me about because mistakes happen. I asked whether it concerns them at all that I had Some of the spinach Cooked in plastic & He asked whether I don’t know that mistakes happen. He was dismissive & told me I could do whatever I want. He blamed his staff and called them useless, took no responsibility & didn’t bother contacting me even to apologise. If this had happened only on Friday I’d attribute it to a bad day, but his attitude was worse when I followed up on Tuesday, & he was surprised that I even complained