Economy Car Rentals-Do they actually exist??

My wife had some time ago made a booking with Economy Car Rentals (ECR ) for 1 to 3 August '25. ECR duly confirmed the booking by email. On arrival at Oliver Tambo, we spent a fruitless search of about 30 minutes for their offices. By pure coincidence, someone suggested that we go to the Bluu offices, and it turned out that ECR was trading through Bluu. ECR never communicated to me that they were in fact, not independent rentals. This was most annoying. On their website ECR has no email address for customer affairs, which indicates how much they care about their customers. and seem to be avoiding Avoid them