Car booked in for panel beating 11/04 by Precision and Sons

I am being moved from pillar to post by Precision Motors and Mercedes Benz South Africa over the status of repairs for my vehicle that was taken in for panel beating on 11/04 and now on 05/05 I find out that some of the parts are due to arrive from Germany on 19/05 then repairs on my vehicle will resume. I am being made to look like a fool and being misled by both service providers who send multiple emails with car jargon which is meant to confuse me as am not a car specialist neither do I wish to be one.

I am struggling to understand why I was told to bring car in if the parts are not available and only find out there is confusion when you start asking questions.