Default Enrollment Formula is only getting called for 2 plans out of 7 Plans under medical plan type

Summary:

We have created a default enrollment formula and attached it at a plan type level ( Plan type is Medical)

under "Default Enrollment Formula" setup for the NewHire Life Event ,

Under medical plan type there are 7 Plans but the formula is only getting called for 2 plan types and not the other 5 plans.

We have ran the "Evaluate Life Event" process for the eligible employee ( Parameter # "New Hire Life Event" , Person number)

but the formula is not getting invoked for the plans the employee is eligible for. Our understanding is once the formula is invoked for each plan under the PlanType=Medical, based on the plan type and union attribute the default enrollment flag will be set as Y.