I'm The Grumpy Old Troll

I'm the grumpy old troll who lives under the bridge
Hey, I'm the grumpy old troll who lives under the bridge, who's there?
If you wanna come over, all you have to do is this
All you have to do is this

I'm the grumpy old troll who lives under the bridge
Hey, I'm the grumpy old troll who lives under the bridge, who's there?
If you wanna come over, all you have to do is this
All you have to do is this

Solve my riddle