It seems price is picked from your last purchase order...
Can you check the last purchase order for the material and vendor...
B.t.w. Purchase requisition price pick the material price.. It will never goes to the PO price, even you create PO with reference to PR. Its only for valuation purpose...
Price will always take from info record/outline agreement or the last purchase order...
As you have seen the "order price history", system displays 7€ as last price"
So it has taken the last PO price...