Path-
custom/modules/YourModuleName/clients/base/views/record.php
if not Exist Copy or create path from
modules/YourModuleName/clients/base/views/record.php
array (
'name' => 'panel_body',
'label' => 'LBL_RECORD_BODY',
'columns' => 3,
'labelsOnTop' => true,
'placeholders' => true,
'newTab' => false,
'panelDefault' => 'expanded',
'fields' =>
array (
find panel_body array and change columns 2 to 3 or 4 As your wish.
Final- repair and rebuild.