Samsung not able to assist!

I have a samsung galaxy s4 on contract, its been over a year into my contract and I was unfortunate to have dropped my phone and the screen has broken. I took the phone into the samsung service centre in nandi drive and was advised to fill in a form and wait in the queue. When I advised the consultant that my screen needed to be changed she told me that samsung cannot repair my phone unless I pay for it! My phone is still under warranty but cannot be fixed by samsung as she advised that samsung requires all their screens back. Due to the phone falling at night outside, I hardly think that anyone in their right mind would be able to find the pieces to the screen, not to mention it was not stated anywhere that a customer needs to return the broken screen! This is ridiculous and now they expect me to pay close to R2000 to fix my phone. I was extremely happy with samsung until now and I refuse to pay for the phone to be fixed for such a poor excuse.