Hi @jaros,

We understand how essential the QuickBooks and Google Calendar integration is for daily scheduling. To explore other options, you'll want to consider utilizing a Third-party app or contacting Google Play's support team directly. They can provide the most accurate guidance and address your issue well.

You can explore using a third-party app to sync your calendar with QuickBooks, offering similar functionality to Google Calendar. Let me guide you on how to integrate apps with QuickBooks Online (QBO). 

Here's how:

1. Log in to your QBO account.
2. On the left corner go to Apps and select Find apps.

3. Click the Search Bar or Browse categories to find apps that suit your business needs.

4. Follow the instructions to install the app and link it to your QuickBooks account.

Additionally, you can customize invoices, estimates, and sales receipts in QuickBooks Online which gives you the freedom to align with your personal style and brand Identity.

Please know that we're here for you. If you have any more questions or need help with your invoices, please reach out to us in our Community forum. We're focused on finding solutions to your concerns.