Form Personalizatin:Navigate to distibutions block from when-validate-record trigger

Hi

In the personalization of Requisiton form in purchasing,I need to navigate to the distributions block from the when-validate-record trigger at lines.It is not being achieved by the go_block

The requirement is such that if some conditions do not fulfil at the lines level,on validation the distribution block should open up and charge account needs to be entered.

Please help me on this issue.

Thanks