Third, it will most likely be the same on mobile, so you can handle this from there as well to add your retail business to Google and correct Google maps listing.
Fourth, you will arrive at Google My Business (you can also start here) which will attempt to confirm the business based on the information they already have, seen below.
Fifth, check the box, and hit continue.
Sixth, you get a call to the number listed which you can accept a code when you answer the call. If they need to confirm the address further, they will send a postcard with a verification code on it that you will need to come back to enter it in. Access it here: business.google.com
Seventh, just make sure you enter the code in when they ask to continue.