At the time of doing 501 movement type, have you given reference as schedule agreement number ?
Have you checked the Purchase order history for the schedule agreement line item ?
501 movement type is just quite same as 561 movement type and it is treated as initial stock upload. This movement type will not update the schedule agreement history. Hence it will not update the ME3L report.
You have to Create a Goods Receipt for the Scheduling Agreement by using movement type 101.