Workflow not re-triggering

Hi All,

I have a workflow e.g. PO workflow.

Currently workflow triggering when it got created. But not re-triggerring when it changed.

Workflow will trigger once PO create and the same workflow should wait until if any one change the PO. If any one change the PO, I have to perform checking of some conditions.

I used "Wait for Event" but it is not re-triggerring. Provided as below:

Container Element = ZBUS2012

BOR = BUS2012

Event = Changed

Do I needs to make any entries in SWE2? If yes, kindly let me know what entries I have to make.

Thanks.