Panelbeater Excessive Repair Time

Our car was sent to Auto Collision Centre in Edenvale on the 14th May 2019, to date (13th June 2019) the car is lying there stripped, the excuse - they cannot source the bumper, in the meantime our car rental expires, because it has been 30 days and no one can tell me when the car will be ready, neither the panel beater or Outsurance who initially referred us to this panelbeater. Would love to know how they vet their service providers, because 4 weeks for an initial quote of R11 000 damage to the right left side of the car seems a little excessive. I believe they have had to order a new bumper as they were unable to repair the existing bumper surely they should have known this on the 15th May 2019 and started the process and not left it to the 6th June. I am furious, with both the panelbeater and Outsurance.