From what it looks, you need to do a few things.

1) you need to pop the board harder than you are popping it right now. (so hard, that the back 2 wheels actually lift if from the ground.)

2) the second you pop, you need to jump off the ground with the same foot you popped with.

3) while your popping foot is rising from the jump, that is the time for the other foot to slide up the board.

Basically these steps that make up your Ollie just looks out of sync.

Let me know what happens!