Difference in cost between the standard cost for OSP item and the PO generated

Hello, I created an OSP Item for an OSP operation work orders - Maintenance.

I created the standard cost for the OSP Item as 50$. When reviewing the dispatch list for the outside processing operation and then chekcing the Purchase order created, the amount of the PO is generated automatically as 10$.

And when I completed the work order, I viewed costs, the cost of the operation was 10$ instead of 50$.

Please advise how can we fix this.

Thanks

Victor Chrabieh