ax 2009 "hanging" workflow steps

Hi, i have following problem:

I have a workflow with 2 steps - step1, step2

each step has approval based on role with option that only one user is needed to approve to get to next step,

When WF starts it goes to step 1, creates 3 work elements with status pending, if someone approve, rest of work elements changes to finished, and goes to next step, but if any user delegates someone else to approve, and that person do approve, work elemnt of delegating user changes to finished, WF goes to step 2, but rest of work elements from step 1 are still pending.

I’m quite fresh when it comes to WF, so here is my question, how to trace and fix this bug?

regards