My name is Olga Lucia Perez please help me because we are trying to post invoices and it does not allow us to do so.

Hello, olga-perez. 

I would like to know if you received an error notice when attempting to post an invoice. In this manner, we can examine the issue and potential fixes.

In the meantime, let's access your QBO account using a private browser to check if it's a browser data issue. This can help us rule out any cache-related issue that might've caused the problems. Use these shortcut keys to open it: 

• Google Chrome: Press CTRL + Shift + N.
• Safari: Press Command + Shift + N.
• Mozilla Firefox: Press CTRL + Shift + P.

If the steps above work, I suggest clearing your browser's cache to boost browser-related issues. Some stored data on your browser can impact the data being transmitted, thus causing some unusual responses. 

In case private browsing doesn't work, I'd recommend using different browsers. They'll provide you with the best and most secure experience with QuickBooks. For more details, please see this article: System Requirements For QuickBooks.  

You may also want to visit the pages below about handling customer's transactions, sales forms, and reports. 

• Invoices and payments
• Various Reports

If you have other questions or concerns about creating invoice and other tasks in QBO, let me know in the comment below. I'll be more than happy to help. Have a nice day!