I have just come back from Asda and found an item on my recepit - anyone ideas

It just says '2' then the barcode 505085490574 than a price
- I searched my shopping - ?

to do with site maybe?
www.asdapriceguarantee.co.uk/

Thanks. There was nothing to input a barcode in but remembered that cereal was not listed - found what I had paid for.
Thanks beer_money. The site did remind me to check the price guarantee tomorrow.