Click the empty data block get hang

I have created a header and detail data block plus a search block to query data and update the detail block item value.

Its work find to query and update value. However, I open the form without query any data and click the header blcok the forms get hang.

I check the database session, it seems query all data from the db but I'm not sure.

Anything I can do to prevent user to click the empty data block?

Thanks in advance.