We have been on Pinterest for years and a verified merchant for a very long time and then recently not. We cannot seem to get any answers as to why the status has changed.
In your dashboard as well as your email you should have gotten a notice of removal and the reason why. It will also allow you to appeal after you make those changes.
Here is how you should be able to find this out.
At the top of your business hub click where it says "verified merchant"
That will open this window & you can click "view issues"
Form there you should be able to submit an appeal after you fix the issues.