in Ap invoice grid is showing no value when send for approval

Dear Experts,

There are 3-4 purchase invoice send for approval when it is open by approving authority the detail grid i.e. where the item details are shown is blank only gross total and net total in footer is showing value and header values.

This all four invoices are of same vendor, invoices punch after those invoice are showing proper values.

what could be the reason ?

Thanks & regards

Kamlesh