"apm.save.problem, update.go" when trying to save incident ticket

Hi, I am currently running SM9.21 Windows.

 

I have created a button which fire a wizard which does the following:

1) Open a new form to prompt users to attach a file

2) Wizard exit and bring user back to the IM.update.incident form.

 

User are required to save the incident ticket to save the attachment to the form.

 

This works out perfectly if users perform the above action in a continuous action. The problem appears when user opens the wizard and waited for a couple of minutes before attaching and exiting the wizard. When user tries to save the incident ticket after exiting the wizard, they get the following error:-

 

The record being updated has been modified since read (apm.save.problem,update.go)

file:(probsummary) key:(number=IM201200000250) (apm.save.problem,update.go)

 

Would appreciate any assistance.