I am having this exact same problem.  Accountant emailed me, I click on the link, get the code, log in and it gives me the "you’ll need to ask your accountant to invite you" screen, even though the email that I got the original email from, as well as the "you are logged in as" email is identical, and I can see my own personal information in there.  This is a technical problem for Intuit, I tried deleting cookies, closing browsers, using different browsers, rebooting machine.  Tried calling Intuit and got blocked in every way at 800-446-8848 which may be the incorrect number for this type of issue, but got nowhere and it hung up on me when I pressed 0. 

@IntuitGabiU has there been any progress on this? My accountant is not super technical and I don't think he will be able to help, but I am going to try with him.