Not able to term or correct prior employer date when adding new work relationship

A new work relationship added to the employee on 4/7 and also marked as primary on 4/7 and now need to terminate the prior employer with effective date 4/6. Received error " You must designate one of the secondary work relationships as primary before the termination". Changed the termed date to 4/8 and tried to correct it to 4/6 received error " Future dated secondary work relationship" any ideas on what's worked to correct or terminate the prior work relationship with a date that is earlier than the new employer start date?