Terrible service !!!!

I submitted a claim through Naked insurance and I was instructed to take my vehicle to Major 2 auto body repairs which I did on the 8th of April 2024. Mind you this was for minimal damages, no internal damages whatsoever. Whilst it was there they have given me 2 completion dates which they didn’t stick to. Last week Friday they advised my vehicle would be ready for collection on Monday and I advised them I will not be around to collect but ll do on the 6th of May. Today they called advising me there is one part missing and the ETA for that part is June. My question is the time they gave me those completion dates did they not know the part is not available???they are really taking me for a ride and they obviously expect an excess for this terrible service wow.