Out of stock on baby bottle teats for months on end!

I have purchased 7 Phillips avent baby bottles and cannot find teats anywhere as they are continuously out of stock nothing in store or online (takealot, Dis-Chem, clicks). I called Phillips customer care line and was given the contact details of a lady by the name of Natasha, who doesn’t even respond to messages. I’m so disappointed and I regret ever choosing this brand for my baby. what am I to do with 7 bottles I cannot use?