Very same issue. It's a link to my business profile, and it just stopped working? If you let the camera highlight the QR code, then press the QR code at the bottom right of the screen(see attached photo), you can "Copy Link" and then paste it in your browser, but that's just not a feasible request to ask of your customer.
I'm here hoping someone from Apple will be able to answer this. I have hundreds of stickers with my QR code on it, and they're worthless, now.