There are two types of time. Clock time and psychological time.
Clock time is timeless. You are in the present moment. You access past or future when needed. Deal with it for practical matters. Once done, you move back deeper into the present moment.
Psychological time is when you identify with the past or keep projecting into the future. You are no longer in the present moment. The past or future consumes you.
Happiness comes when you free yourself from psychological time.
Gratitude to Eckhart Tolle’s teachings from where I learnt this.