Paid or unpaid shopping listings requires you the merchant to follow the same exact policies.
The most common issues are:
You can ask Google for specific examples of policy violation. To do so ask here and check the box, I need more info : https://support.google.com/merchants/contact/suspended
If Google replies with vague answers or when they say, the decision is final. Then your account is permanently suspended.
If you provide the community with more detailed information such as the website URL, we may be able to provide further guidance.
Hope this helps.