Returning Multiple Values with the same date

Hi htbull_,
Thank you  for reaching out to the Microsoft fabric community forum.

The issue you are facing is because SELECTEDVALUE only returns one value, so it doesn't work when multiple members share the same join date like 10/01/2020. To show all names for a selected date, you can use the CONCATENATEX function along with USERELATIONSHIP to list them.

Members Joined (List) = 
CALCULATE(
    CONCATENATEX(
        VALUES('Member Current Info'[_MemberName]),
        'Member Current Info'[_MemberName],
        ", "
    ),
    USERELATIONSHIP('Calendar'[Date], 'Member Current Info'[_JoinedDate])
)

I tested it with my sample data, and it worked fine. Please find the attached screenshot and Pbix for your
reference.

If this answer was helpful and pointed you in the right direction, please consider clicking "Accept as  solution" and kindly give a kudos it may benefit other community members reading this thread. If you have any further questions, feel free to let us know.

Best Regards,
Harshitha.
Community Support Team

Hi htbull_,
Thanks for  the follow up

To display each Member Name on a separate row for a specific date, you don't need to use a CONCATENATEX measure. Instead, simply use a table visual. Add the table visual, then drag in Calendar[Date] and Member Current Info[_MemberName]. Also, ensure that the relationship between these two tables is in an active state for the data to display correctly.

please find attched screenshot for your reference 

I hope this information is helpful.

If the answer is helpful, please click "Accept Answer" and kindly upvote it.
Regards, 
Harshitha.