Hello, Sergio.

Dealing with a potential hacking issue involves a comprehensive investigation. Thus, I recommend contacting our Phone Support team. They have the tools required to check your account and identify the underlying cause of the issue.

Here's how:  

1. Log in to your QuickBooks Online company. Then click Help (?).  
2. Click Talk to a human.  
3. Choose Talk to a Human.  
4. Type your concern.  
5. You have two options: either request a callback or message an agent to speak with a representative.

To ensure that you'll be assisted immediately, I recommend checking our support hours before performing the steps. 

I'm adding this reference for tips and guides on how to recognize official Intuit correspondence and websites: Identify suspicious activity, phishing scams, and potential fraud.

Keep me posted if you need assistance with your QuickBooks account. The Community is always here to assist you.