First, verify that you received an invitation by email. If not, ask the owner of the family subscription to resend it by clicking on “Resend” and ask them to check the email they used. If they made a mistake with the email, they can delete the invitation by clicking on Cancel invite and then send a new invitation to the correct email address.
Another reason could be that the invitation expired. It means that the owner of the family subscription cancelled the invitation.
Also, if you already have a streaming subscription to Qobuz, you will first have to cancel that subscription and wait for the paid period of validity to expire. You can find this date in the My Streaming Plan tab. If you’re part of another family, you will need to cancel your family membership to join the new one.
The Qobuz Family Plan are available only in the USA and the UK.
If you have additional questions, contact customer service directly.