Wesbank vehicle authorizations bad service

Ii have been dealing with Wesbank for authorization to service vehicles for 40 years and their service has deterated so bably. You wait on the phone for ever when you get through they tell you that they will send you a authorization via email which also take a long time if our customer needs the vehicle back the same day their service been so slow create a problem for us. When the vehicle is eventually finished we then email the signed invoice through for payment which takes a long time. We then phone to query why we have not received payment. Will no longer be doing work for Wesbank Fleet