Hi,
You can use two option to verify what is the source of price coming in Sales order ...
1. Use 1.10.1.13 (sopiwiiq.p - Pricing What-If Inquiry (S/O))
2. Use 1.10.1.17 (soppiq.p - Sales Order Price Inquiry)
Once you identified the source, then it become very easy to resolve the issue.
Regards,
Subhendra.