21 DAYS PAST STILL NO PHONE

Just want to start off by saying that I love the service and people working at Tyger Vally . I have booked my LG Flex in with them for repairs as my speaker just stopped working. They took the phone in asking me to sign on a form to hand it over and gave me a demo Nokia for time being and PROMISED me I will have my phone back within 21 working days. I waited patiently for them after all they helping me fix my phone, but its already passed 21 days and almost 30 days now and I still have no heard a word from them. This morning I phoned Call Centre they put me trough to Repairs. The lady answering asks me for my ref nr which I obviously do not no any thing about and I tell her I haven't received any thing like that . I tried explaining to her that I did not receive any thing like that by which she replies but that's customer negligence because I just gave my phone in and left the store so she can't help me. because it is customer negligence. I had no idea they had to give me any thing as I asked and they the sales person assured me that everything is OK so I assumed I had everything I needed. this is becoming a big mess because seems to me I'm never getting my phone back.