Install adjtimex by entering the following commands in the terminal:
sudo apt update sudo apt install adjtimex
kernel time variables configuration utility
This package provides a utility to manipulate the kernel time variables. For a machine connected to the Internet, or equipped with a precision oscillator or radio clock, the best way to keep the system clock accurate is using NTP (Network Time Protocol). However, for a standalone or intermittently connected machine, you may use adjtimex instead to at least correct for systematic drift. It can optionally adjust the system clock using the CMOS clock as a reference, and can log times for long-term estimation of drift rates.