Enfore commit by user before navigating to next block

Dear All,

I have a custom form in which I am using master-details relationship but in actual there is no foreign and primary keys impelemented. My requirement is before going to any child block, a prompt should remind user to save record. I don't want to use commit_form. I want user should save changes if it is a new record or any change has been made to existing record. I tried when validate record trigger with builtin :SYSTEM.RECORD_STATUS IN('INSERT','CHANGED') but it did not work. Message is appearing appropriately on going to next block but it is not allowing user to save record.