I understand that you are experiencing some issues with accessing an old store, and you are wondering how you can contact support. I would be happy to explain how to contact our team.
You mentioned that you don't know the old store that your Facebook is connected to. We actually have a recovery tool here that you can use, where you can enter in all of your email addresses, and it will send you an email with the details of any stores registered to that email address. Feel free to try that, as it may help you to find the old store. You can also then reset the password if necessary by following along with the instructions here.
Are you seeing any error messages when trying to setup Facebook on your new store? Feel free to let me know what is happening, and if possible send a screenshot of the problem and I would be happy to take a look and steer you in the right direction.
If you would like to speak to our support team directly, you can do so via our help center here. The look and feel of the help center has changed a bit in recent months, but the main functionality remains the same. You will need to interact with the chat assistant in the bottom right, however you can enter prompts such as 'live chat' and it should give you the option to connect with our team.
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