put detail on header block , but can not see detail

Hi all ,

I am a newbie to oracle/develop2000 , and meet a strange problem : I have create a new window , put a "header" block onto it , then put a other block onto the previous block to present the details information , it seem like a bill-entry form , include a header record and some lines of detailed information. It seemed properly when design , but when I want to run it , only header block can appear , the "detail" block has been hidden !

How to resolve it ? how to make the "detail" block visible ? Any advice will been appreciated !

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lcl
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