Hello does not give me the correct time [time constantly changing] how many times I manage time, this auto-change to another erroneous time to me when restart Any suggestion?
If the time is really erroneous and illogical after each restart and your computer is several years old it is most probably the small buffer battery on your mainboard that needs replacing.
If the time is wrong by hours or half hours (might even be quarter hour if set to some exotic time zone) it is most probably the time zone that is not set correctly and ntp overrides your manually setting the clock. In this case run sudo dpkg-reconfigure tzdata to set the correct time zone of your location.