Fly inside a sweet and no urgency from the brand

I sell sweets at a school, my sweets are different flavored smoothies, they are written 72 pieces per packet, I normally don't count but at times I do and it's never 72. I also find empty packets from time to time and I've reached out to them and never was I helped. This time, a learner found a a fly inside a sweet, she said" it tasted funny so she took itut her mouth Low and behold a fly, I contact tiger brands and they just promise me a voucher to but other sweets like really??. They never sent the voucher.