Hello guzzelmo,
Sorry for the inconvenience you're experiencing. Could you please clarify how you're currently implementing the Open Graph option? If you're using the template settings, please note that those only apply to articles. For SP Page Builder pages, such as your homepage, you'll need to enable Open Graph directly within SP Page Builder.
Here's the relevant documentation for the correct setup:
SP Page Builder – Options Documentation
This should allow you to add an Open Graph image to your homepage. If this doesn't solve the issue, please reach out and I'll look into it more deeply.
Best regards