Hi GLLTD!
I hope you are having a nice day! I read your other post, and I understand that you want to use the same email address for the QuickBooks Online subscription, but the system won't let you because it's already in use. I have a short explanation about this.
The email address and credentials you use when accessing your QBSE subscription are associated with your Intuit account. Therefore, if you want to add a QBO subscription, you only need to sign in with the same credentials.
To add a QBO plan/subscription under your Intuit account:
- Choose a QBO plan: https://quickbooks.intuit.com/uk/pricing/.
- When you reach the Let's get started page, click on Sign in.
- Enter your existing user ID and password.
- Complete the process.
You can use this link to log in to your QBO company: https://c1.qbo.intuit.com/qbo1/login
Feel free to reach back out if you have additional questions in mind.