Creating a shop

Hello, today I decided to create a shop. I thought it would be a simple task using the shop create. Well, it turns out I was wrong. I read the guide on how to create/manage a shop and learned how to use the tools. Great, now I just use shop select to draw my shop boundaries and create the shop. Everythings all good until I try to add to my shop. A message pops up saying "You are not in a shop!" Okay, maybe I did something wrong. I draw the boundaries again and attempt to create a shop again. This time, a message saying "A shop already exists here!". I don't know what's wrong and I would like to have my shop up and running as soon as possible. Can someone please address this issue?

Thanks,
AmboF1

Its hard as fuck to make a shop >_>

It's easy.
Make boundaries. It must be the Top Left corner to the Bottom Right corner of THE ENTIRE BUILDING. When done, it should be something like 3 blocks tall, allowing usage of the shop. Now do /shop create *YourShopName* and then add your items. I've made one myself, it was very easy.

I have also made a shop before it's a bit confusing at first but once you figure it out it's extremely easy.