No label required message while approve/reject leave application

Kindly help to sort the below, i have created a workflow for leave application as
in States
1)state (draft), Allow edit (employee)
2 ) Approved Dco status (1) allow edit (leave approver)
3) Rejected doc status (2) allow edit (leave approver)
in transition rules

  1. draft approve approved leave approver
  2. draft reject draft leave approver
  3. Approved approve approved leave approver

While approving the leave application no action been taken because receiving NO LABEL REQUIRED message