accounts - no invoices send

On September 3, 2018 I requested to Lancet to send me an invoice for services rendered. Lancet claims response within 5-7 working days . Up till today nothing. No emails , no calls, just NOTHING. Nothing has changed, although promises made by Gabriel, a couple of years ago, to upgrade their accounts department, nothing has been done. No invoices, no email or snail mail , no calls. It all is the same as always. ***********? Most businesses send their invoices via email , but Lancet does not do this,. They just do not send invoices. Payments can't be done if you do not know how much is outstand. Please Lancet when are you going to do the implementation of sending invoices?