Click on the “Approve” function then you will see the options to backflush. Thanks

We normally refer to backflush as automatic issuing of materials. If the material is linked to an operation, it is backflushed when the operation is reported, else you have the Backflush toggle available when receiving the shop order which is done using Approve on the last operation.

If you rather mean auto reporting of operations this function is also available. If you approve an operation which has unreported preceding operations you can enable the Report Previous Operations toggle. If you set the operation to be a Milestone operation this toggle is enabled by default.