Currently some of the codes are not working on the current version of the Lowe's Promo Codes app in the Play Store.
I have an updated version ready to roll out but I lost my developer key when I recently wiped my hard drive. Google support wasn't available over over the weekend but I was just informed they updated my new key but I won't be able to update the app until February 7.
In the mean time I have set up a website version of the code generator and it even created barcodes. Just send me an email with some sort of proof of app purchase and I will send you a link to the online Lowe's Promo Codes generator.