Hi Alex, you mentioned light roasted. Are you sure it is even roasted?
The grassy note present seems 2 point otherwise. The tea might be
baked at the last stage 2 dry off the water content in the leaves, but
roasting it would change its note 2 deep floral with a light roast.

1stly, do you use a gaiwan or a clay teapot to brew it? I suggest a
porcelain gaiwan.
2ndly, how much leaves do you use? I suggest just enough 2 cover the
base
3rdly, bring the water temperature 2 85c & no higher
4thly, pour the water from the side of the gaiwan 2 3/4 full
5thly, leave the gaiwan open till you are ready 2 pour it

Hopefully this gives you a better brew, or you can store the tea away
& taste it again in about 6 months' time...

Kevo