Unacceptable service

My Samsung S5 went into Safe Mode and I was unable to turn the Safe Mode off. I took my phone to the Cresta store where I was told that the small crack on the left hand side of the screen was causing the problem, I was advised to take the phone to the Care Centre in Roodepoort which I did on 16/01/2015 (# ***). I waited ages to be assisted. They then phoned last week to say that a technician looked at the phone and confirmed that it was due to the cracked screen and it would be replaced free of charge under the ADH warranty. I then heard nothing from them until I followed up yesterday, I was told that now all of a sudden there would be a R2200 charge to fix the motherboard. They said the emailed the quote to me, I never received this. Why did they confirm it was the screen that was causing the problem if it wasn't? Why did no one contact me about the motherboard? Why is the motherboard not covered under my normal warranty? The consultant also argued with me about the cover that I receive under ADH Premium and refused to send me the warranty terms & conditions. I would also like the replacement phone that I am entitled to under ADH while this is being sorted out.