Morrisons review: pricing

Hi there, Today I picked a box of Corona beer of 18 bottles £10, which was on the pallet at the front of the store. Front of the store is for promotional products, there also was toilet rolls 24 for £6, washing powder Surf £6, and Corrona beer £10. I looked at the price twice to ensure, but then I got home and looked at the receipt apparently I paid £15 for it 🤨 wish I have notice that while at the check out.
I do understand that some times staff missed it to swap price, but this happening every my visit for around 5 months now. Thats why I am submitting this form on here, as I had enough and annoyed.