My client alraedy has a quickbooks online account and I am trying to connect to it via QBO accountant. It is not working as it says the client does not have QBO.
Welcome to the Community. I'd be happy to help with getting you on your client's account. In order to add a user on an account, you'd have to do this using a browser or the QuickBooks Online Desktop app. Here are the steps you'd need to follow to accomplish this:
Sign in to your QuickBooks Online company.
Click on the Gear Icon > Manage Users.
Go to the Accountants section and click Invite Accountant.
Enter your accountant's email address and first/last name (optional). They will receive an email with a link for signing in to your company.
They will be asked to create a user ID before signing in the first time, unless they already have an account with Intuit Business Services.
Until your accountant signs in, their status on the Manage Users page is "Invited." After accepting the invitation, their status changes to "Active."
Click Next and Finish.
The user would have to accept the invitation through their email for this to work. For more info on users in QBO, check out this helpful article: Add, delete, or change user access. Otherwise, let me know if you have questions. I'll be here to help. :)