Find multiple values based on distinct id

[#1]

Hi,

I am trying to write an expression which would list down the below table of all customers who are not following the below rule.

Rule to be followed is: One Project ID should only have a single Customer.

Eg:

Project ID	Customer Name
112	SERVICES PRIVATE LIMITED
112	GlobalSoft Pvt ltd
345	Tech Pvt ltd
345	UI PRIVATE LIMITED

I tried with aggregation function but couldn't figure out how to get the above solution

=aggr(if(Count(DISTINCT([Project ID]))=1,if(count(distinct([Customer Name]))>1,[Customer Name])),[Customer Name])

Please let me know the correct formula to achieve this

[Anil_Babu_Samineni]

What is the logic behind on this? How to justify which one you want to show in UI