With Beas 9.2 (5.48), there's an issue that will cause Material Issues/Reservations/Allocations to not be completed successfully.
The situation does occur when multiple users are creating Material Issues/Reservations/Allocations at the same time. It is most likely to appear if one user keeps the Issue/Reservation/Allocation screen open for an extended amount of time, e.g. by selecting a huge amount of lines manually, one by one.
We fixed this issue in Beas 9.2 (5.49) and recommend to upgrade to the latest version!