I use #43# to turn off call waiting, it works perfectly during the day and evening but overnight at about 3 AM it seems to re activate by itself. I also turn it off via the toggle in Supplementary Services and the same issue happens. I am on the Vodafone network. I have had this issue on 2 Samsung phones but if I put the SIM in a Heuwei phone there is no issue. I have spoken to Vodafone and of course they say it is a Samsung issue!!
Any ideas on a permanent fix would be appreciated.
Android version 9
By Call Waiting I mean that when I am on a call another caller can ring call me and get through. I want the second caller to hear an engaged signal when they call me so I am not being desturbed while on a call to another caller.