Bad repair service from top cell phone company in the world

I took my cell phone to Huawei Melrose Arch to have the battery replaced on 19 December 2019 and was informed that the phone will be ready on 23 or 24 December because they are very busy. On 24 December I used Huawei's online chat portal and was that the battery is still not replaced and someone will contact me soon to inform me when the phone will be ready. On 2 January, I again used the online chat portal and again was told that they will enquire where my phone is and contact me when my phone will be ready for collection. Nobody called. On 13 January 2020 I used the online portal again and was promised that my phone will be ready for collection on 15 January 2020 and that they will call me before 9am on 15 to confirm that the phone is ready. On 15 January 2020 I used the online portal to enquire if my phone was ready for collection or not. Again I was promised that they will contact me by 13h to inform me when my phone will be ready for collection. By web nobody called. I again used the online portal to enquire where my phone was and then only I was called. I was told that the battery on my phone is still not replaced because they waiting for spares and that they do not know when my phone will be ready. I then requested that the return my phone so that I can find someone else to replace the battery. I am disgusted at the bad service and run around that I received.