Worse experience from a huge company such as Pioneer Foods

I've bought White Star Maize meal the 10 kg one in November 2023. Whilst using it I found small lumps that had black stuff in it but I thought it's just me being dramatic. Sometimes things go wrong and maybe this was one of those times but the more I started using it the more of these lumps I've found and the worse it got. At the bottom of the bag I've found this huge one that looked like it's germ infested and I immediately felt sick cause how can you sell something that's that disgusting to people and expect them to eat it. So I took pictures and send through my complaint and I followed up over and over again cause no one could tell me why. In January this year that when I heard back from a Tristan Williams from Pioneer Foods thanking me for complaining and said they'll investigate the matter. I responded by asking how so if I still have the bag with all those disgusting lumps and they had more than a month to investigate. And like all the other times they just simply ignored me which is really horrible service. In fact in this case I can't even say I'm complaining about their service cause they've none. They don't respect their customers and all they care about is their customers money and to hell with the rest.