Tiger wheel hassling with warranty

Hi

I purchased a battery from twt just under 2 years ago (still under warranty). My battery was faulty so i took it to the three rivers branch on 4/5/2019. when trying to test the battery the technician could not get any reading and said that the battery was faulty and needed to be replaced. I was told that the branch did not have stock of the battery so i agreed that they can order it and i will come back to fit it in, no one even called back to confirm that the battery was in stock and i kept following up daily. Eventually i got through on 8/5/2019 and was told my battery was in stock, the salesman said he would like to test it again so i agreed and the slip clearly said replace battery (which i kept a copy of), yet he said that it is probably my charging which is a problem as that is low. I was told that i need to get a report from a mechanic to "prove" my claim, yet when i fitted the battery no one wanted a mechanics report on my car!! i tested the battery on my other car which mind you has been running perfectly for years and guess whats, the battery drained out after driving it for a few days, i find this service to be extremely poor that when you want to get a sale you help a customer but when it comes time for warranty you hassle and look for excuses. This needs to be sorted out asap as I work in jhb and cannot keep on running around for service.