Customer Tax Invoices not update

Unable to edit a customer tax invoice by deleting items. It keeps loading. after retrying more than 10 times without any change, when it eventually deletes the item entries, the hours under 'Time Entries, Invoice time' increase dramatically, i.e from 8 hrs to 124 hours. and it is impossible to update these hours on Time Capture view. I can't send my clients invoices, this is frustrating!!!