Employees are defaulting to Decline Medical during trial OE

This is our second year using HCM - Benefits to enroll in benefits. Only the rates and plan names have changed from last year's open enrollment period. We have begun trial testing and are seeing that medical is defaulting to Decline Medical enrollment regardless of previous year's elections. The enrollment rule is set to "Current - can keep or choose; new - can choose" in the Scheduled: Open work area so employees should expect to see the previous year's elections. What would be causing a default to decline medical?