Commitment in Service Contract

Hi,

In our organization, we create Service PR with Acct Assit as Internal Order/WBS element. The Service PR shows the the commitment. Now we create Contract referencing to this PR. However system doesn't flow the commitment from PR to Contract. The commitment still remains with PR.

Later we create multiple PO referencing to Contract.

This creates double commitment (both via PR and PO)

Is there a way to have commitment at the Contract.

Please note we cannot change our process.