Battery replacement

iPhone emailed to say my model phone needed a battery replacement and this would take three to five working days. On 17 th January my iPhone was assessed by a consultant at the Apple Store Friedman Drive Sandton and I was informed a new battery was imminent. In good faith I left it for the service. Now almost two weeks later, ten working days, they can still not tell me when I'll get my iPhone back with the new battery. They keep emailing that they are awaiting stock.... I am a widow, have only a Blackberry as a temporary replacement. I am without WhatsAp to communicate with family around the world and stuck because Uber also not compatible with this phone. It is proving a most stressful, unhappy, difficult time for me. My iPhone battery was still operating when I handed it in, so it was not necessary to take it when they had no replacement battery in stock. I find it totally unacceptable, but Apple personnel do not seem to care and are unprepared to give me a loan phone.