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