Approval Workflow not working if base salary is not updated in Change Salary

Summary:

Based on our requirement, we configured the rules if there is change in salary then it should go for approval. These rules are working fine. We have rules for Linemgr, Second Level Mgr, HRBP and HROPS initiators. But sometimes for new hires Salary is not updated. When the salary is not there for any employee and we do change salary, the rule is failing. At the same time Administer Salary is also following the same rules and hence if the initiator does the change salary without having the base salary, the rule is failing. can