The ‘pursuit’ of happiness is thus named because you keep pursuing it, never attaining it. Happiness (or unhappiness) is transient, it is an emotion caused by an external stimulus. Something makes you happy means some other thing makes you unhappy.
Seek stillness of mind, not happiness. Seek calmness as your default state. Seek to be the lake that is still by default. A pebble might cause a small ripple, but that is temporary; you will soon be back to your default stillness.
We all have our pre-programmed default settings of contentment; some of us are born with the ‘low’ setting while others are born with the ‘high’ setting. Focus on raising that default level via self-awareness, meditation and compassion. i.e. Seek to improve the baseline, don’t chase the spikes.
Add a layer of ‘mindful awareness’ between stimulus and response and make it a habit to seek peace over happiness.
Equanimity is under-rated. Happiness is over-rated.