I don't know ITs name...

Last weekend  (Sunday) was a day for me to rest...meaning I no need to wake up so early. Don't ask me what time I woke up.....(malu to say out).
While cleaning my car porch, I saw this beautiful flowers blossomed. This flower was given by my MIL when I moved to my new house, a year ago.
My MIL bought the seed (look like big onion) from Brastagi wet market, a resort place in Medan during her first time visit to Medan.
Frankly speaking, I am not keen in gardening...so what I am doing everyday is watering this plant and plucking away those dead leaves.

.....too bad these flowers can only last less than a week..don't when it will blossom again.
I don't even know the name of this flower...Who can help me?