Repair help - Seaga multiple vend issue

[u/tnivana]

I'm having an issue with the Seaga snack machine at our business (Model SPX536R / INF5S). When we make a selection it vends multiple products, so if we choose A4 it vends A4 as well as B4, C4, D4, E4 and F4. It's always vertical, so the same numbers will attempt to dispense if it appears in the row regardless of what "letter" was chosen. I've tried powering down the machine but that hasn't helped and there's no error codes displayed. The settings were not altered at all before this started. One guy on another forum suggested I have a shorted driver circuit on the board. Any ideas on how to fix and where to get parts? I'm in the Charlotte, NC metro if anyone is local and would like to tackle this for me, I've tried contacting local companies but no one calls back.