Objective-C Lock screen media controller hide next/prev buttons

Question

I am developing iOS media player app with Objective-C. There is lock screen player and I would like to hide or disable prev and next button. Here is my code:

[MPRemoteCommandCenter sharedCommandCenter].previousTrackCommand.enabled = NO;

[MPRemoteCommandCenter sharedCommandCenter].nextTrackCommand.enabled = NO;

[[MPNowPlayingInfoCenter defaultCenter] setNowPlayingInfo:songInfo];

But prev and next buttons are still visible. Can anyone help me disable or hide these buttons?