Value based on 2nd relationship

Since My original post is hidden by the system, I have to post this again. I am building an app
with 3 Collections
1 Users
2 Organization
3 Members
Organization —> Members. is 1 to Many Relationship
Organization → Users. is 1 to many relationship
Users → Members many to 1 relation( technically 1 to 1.

When the user sign up , he can complete sign up only if he is a member of any organization. Otherwise he cannot complete the sign up . This is my goal.
For this purpose I made my sign up in 2 screens , Sign up 1. actually does the sign up. Sign up 2 basically update user collection , with the organization the new user is a member of ( same email) .
so in the second screen, I have member drop down which populate with only one value which is the member name same as user full name If this new user is a member of any org. Otherwise he cannot continue . if he is a member, select his own name from the member list and come to the second drop down which is the org he is a member of . This drop down popluate only org name which he is a member of . I used the custom filter : Logged in users → members → Org in this field value. But it shows all values in the list. user. —>. Member —> Organization must be a single value. But Not sure why it is just showing all the org in the drop down. instead of showing only one org which member belongs to. Can someone help
George