DURATHERM THE WORST SERVICE AND NOT HONOURING WARRANTY

The worst service and experience ever. I reported my geyser as faulty through Standard Bank which immediately send out a plumber to check the geyser. Upon checking the geyser they informed me that thermostat and element is faulty. The manufacturer, Duratherm must repair the geyser as the geyser is still under warranty. The geyser was installed on the 19th of December 2019 and the warranty is 1 year. After numerous calls to the bank I was only informed today, 3 days later that Duratherm informed me that the thermostat and element was only under guarantee until last month. Unless I don't know how a calender work it is not a year. I have tried to contact the manufacturer on *** but without success. They can be contacted. This is the worst service and a ******** act as the manufacturer is not honouring their warranties. I need to be contacted asap and the geyser must be repaired asap.