Is it Hypericum genus?
I notice a whorl of four leaves.
Is it not Plumeria? Please verify!
I guess it is alamanda flower
is it Frangipani ? the soft edges look like frangipani AKA Plumeria
No. Not Plumeria. The arrangement of petals is different in both the flowers, apart from the color. Also, compare the leaf shape and size.
This is allamanda cathartica
Here is the description of flower that matches with the picture- The large flowers (7-11 cm long and 5-7.5 cm wide) have five bright yellow petals that are fused together at the base to form a tube (i.e. corolla tube) about 4-8 cm long. This tube has reddish markings on the inside and is topped with five spreading petal lobes. The flowers also have five sepals (8-22 mm long) that are fused into a much smaller, greenish-coloured, tube at their bases (i.e. a calyx tube). Each flower also has five stamens that are joined directly onto the inside of the petals (i.e. adnate to the corolla tube) and a long style with two small branches at its tip. The flowers are borne in loose clusters (i.e. cymes) near the tips of the stems, each containing about ten flowers. Individual flowers are borne on short stalks (i.e. pedicels) about 5-7 mm long and the petals (i.e. corolla lobes) are folded and twisted when in bud. Flowering probably occurs mostly during spring and summer.
Reference Allamanda cathartica
This is Allamanda Cathartica
Commonly known as Yellow Allamanda
Dicot
Flowering in spring and summer
Sand,Loamy & well drained soil
Substance extracted from this can be used as a pesticide
Seeds, milk and bark are poisonous can cause abdominal pain if consumed