We run more tests and decided to change some of the parameters. When we leave the values as described above, MRP doesn't calculate correctly. But when we change parameters to:
Safety stock=2000
Reorder point=2000
Maximum Inventory=4000
Order multiple=1000
the system doesn't suggest overstock anymore and inventory is included. In this particular database safety stock and reorder point need to be the same. When we changed safety stock to anything else, the system start calculating wrongly. Unfortunately, we haven't been able to replicate it with Cronus.
thank you!