We want to help you with your questions about downloading data in QuickBooks. However, we need more information about it to provide the right resolution and to get this sorted out promptly.
Are you trying to switch from the Self-Employed version to QuickBooks Online? Which part of the process you're getting a prompt that the password is incorrect? Any additional details you can provide will help ensure a timely solution on this.
While waiting for your response, I suggest resetting the password if you're referring to the login credentials.