Why do they call me Syahrini?

It's happened when I was teaching in SMP Muhammadiyah 7 Yogyakarta.
I was so confused when there were some students of class eight who called me, "Syahrini... Syahrini... Where's Anang Hermansyah??
Because I don't teach them, so I don't hear them.
BUT...
A few minute later I realized that they Call Me... SYAHRINI...