Before we start, could you let me know if they encountered any error messages while trying to accept the invitation?
In the meantime, since they have already tried reinstalling the app, please have your employee ensure they are using the correct email address or their existing Workforce login to accept the invite. They should also make sure they are opening the most recent invitation you sent.
Please note that if their email is already associated with a QuickBooks Online (QBO) account, they will need to use a different one to ensure each user has a unique ID for security and system tracking.
You can route them to this article for detailed steps on accepting your invitation: Set up your QuickBooks Workforce account.
Feel free to reply with those details, or let us know if you require any further assistance in the meantime.
