I tried re to this quite awhile ago but do not see the reply or a response so will try again.
The time changes seem random, the date & time is always off including hours & minute. There does not seem to be any difference if he is at home on wifi or on wifi at another location (we just spent a week w/relatives & he had wifi there) The date & clock moves ahead but is usually behind by days. It will sometimes jump ahead to a new date & time but it seems to happen when he isn looking right at it to notice so we can't say if it happens when he is using it or has just used a certain app etc.
The phone has started to "freeze" as well & drops the wifi in our house.
Because of this he is unable to use many functions of the phone making it unreliable. In particular he cannot use the alarm function of the phone which is a "tool" of the phone that is necessary for him to have & one of the reasons to have the phone. If the phone can't function for what is "necessary" then it's not going to be "necessary" for us to continue to pay for the line, insurance etc.