Purchase Requisitions with Multiple REQAPPRV Workflows

Hello,

We're experiencing situations in which multiple item keys are created for one purchase requisition and we're trying to figure out what the cause is.  I've included a screen shot, below, of one example.  This one requisition has four item keys associated with it and, hence, four separate REQAPPRV workflows. 

If someone could please point me in the right direction as to how to identify the cause and remedy it, I'd appreciate it.

Thanks,

Debby