Worst service ever experienced

We are busy with construction at our property in Plettenbergbay which my mom is overseeing. We ordered custom made doors from Builders Warehouse end of October 2019 when my mom paid the deposit of R50000 for amongst others the doors and building material. She signed dor the specific measurements and to which side the doors had to open. The rest of the money was paid on 5/12/19 in order for everything to be ready and delivered when construction commenced in January. Since then the service has been riddled with incompetence. Initially the complete order was not even delivered. The doors were missing. Apparently someone had accidentally sold our doors. They vowed to get new doors, then they delivered the wrong doors, which were sent back. Then they delivered only one door. Now construction is at a halt as it cannot go on without the door. No one at Builders seems to know how to deal with this. Everytime my mom asks for the manager she is told the manager is not there or sick. Finally she got hold of the manager who then said she was nit af all aware of this problem. Now again they phoned and said that the door in fact had been delivered when we have all the notes and slips with proof that it had not been. Its really insane how this has been handled. Builders warehouse in 3 months have been unable to produce a door that has been paid for. There is still no resolve to this problem.