How to create mutually exclusive system roles?

Hello everyone,

My team need to create two system roles A & B. No user should be able to order or possess both roles at the same time. 

How can I make two system roles mutually exclusive ? 

We have tried to use the "exclude system role" task on role A to exclude role B. But OneIdentity throws an error when we attempt to exclude role A from role B. 

The message mentions an infinite loop. 

Is there any best practise to solve this kind of an issue?