A big thank you to August 6990 for sharing a solution.
If you are encountering issues when trying to verify your identity in Google Merchant Center Next, where just a single-line bar appears instead of the steps, this guide will help you resolve that issue.
Go To Google Merchant Center and click on verify your identity here https://merchants.google.com/mc/products/diagnostics/accountissues
Now click on get started
A thin 1-pixel line will appear; you can now press F12 on your keyboard, which will bring up your developer tools, and select the element selector. If you are having issues selecting it, exit the developer tool and zoom in CTRL + to 175%, then open your developer tools again, and it’s a lot easier to select.
Now select the iframe and change the 1px height to 500px