Need help on defining PO approvals for below requirements

Content

Requirement:

1. PO should route to IT Department approver when an IT Category code is used (All IT Category codes are defined in Procurement category  hierarchy as Level 1). If a Non IT category is entered then it should get auto approved and move onto next stage.

2. Same like above If FA category codes used on PO along with the natural account segment starts with 57XXX then PO should route to FA approvers. (All FA categories are defined in Procurement category hierarchy as Level 1). IF Non FA & non 57 accounts then auto approve in that stage and skip to next stage.

I was able to achieve when a non IT and non FA as well as natural account other than 57 is used as auto approve in that stage but when I enter the IT or FA categories then I was also able to achieve the approvers but at the same time system is picking auto approval as well. so I just need to know how to eliminate auto approval from the IT or FA conditions path.