[Koha] Date Acquired problem in Items

Dear All, I have edited our books framework to make the 952$d field mandatory, as it is our requirement. I have imported a large number of books from our oracle database using this framework. However, when adding an item to a record, the item is not being saved with error that mandatory field is not filled, although date acquired is not empty. When i remove the mandatory requirement form 952$d field, the error disappears and item is saved. I would appreciate support to resolve this problem. With best regards, Naveen Ali ITM-JE (EAKL) Inst Representative for HEC Digital Library Resources. NEDUET, Karachi.