I do not know your business so the below is based on the most common reasons and based on your post.
A general rule is 1 business 1 account. Having multiple businesses that are very similar in niche or products is a violation of Google's policy. As it is considered taking unfair advantage.
Drop shipping is not allowed, as you are only allowed to advertise what you have in stock
Not adding any valid contact details (address, email, telephone and contact page)
Not adding any delivery, returns, terms of service, policy pages
Not adding any payment info in the footer of the site
Hope this helsp.
This is an accepted solution.
Creating multiple accounts for the same business is also a policy violation. As this is considered circumventing violations. As you can understand we community members will not know the real reason and especially when we do not know the account history and what website it is.
So if you can not provide further info, consider contacting Google for more info here: https://support.google.com/merchants/contact/suspended
Yes that sounds correct by design. You can not submit multiple stores, even subdomains to 1 account using 1 Google Merchant Center account, if the top level domain is already registered.
Because when the top level domain is registered, all subdomains can go into 1 account, however the free shopping app does not allow it due to technical limitations. You can proceed however with a paid app, that does not have this limitation.
Alternatively only register subdomains, to each Google Merchant Center. for example.
Instead of mystore.com
Ok, so you should not have any issues, if you do and its an issue with the app, best to contact Shopify support.