HR 2nd level approval for early release

Hello All

I would like to inform you that currently I am serving my notice period and I asked for early release from my reporting HR as since I am last 2 months on bench and I need to join other company however HR always use to said that I went for 2nd level approval for my early release. Any idea how many days usually does take for second level approval why because 10 days already passed and still it's pending for the second level approval. please help me out if it's not going going to approve after 10 days also. Then what should I do whom should I asked for the second level approval please suggest if any have one gone through for the same situation.