HR is not releasing me before my last working day of Notice Period

I am currently serving notice period which is of 2 months. I have already served 5 weeks. I want to get release before 2 weeks in my notice period. I have already informed to HR that I am ready to buyout for 2 weeks or adjust it with the leaves. I have given KT to my team members and completed my pending work items. My Manager is ready to release me but HR is not releasing. My manager has also talked to the HR to release me but they are not releasing. After high request HR is ready to give me 1 week waive off but I want release before 2 weeks. My Notice period policy says: "Employment may be terminated by either Party, by giving the other notice in writing or payment in lieu. The company reserves the right to insist on notice period being worked if necessary due to business requirement however, the option to relieve you from your services before completion of notice period shall rest with the Company subject to adjustment of salary & allowances in lieu of the shortfall in the notice period. Offsetting of accrued leaves against notice period is at the discretion of the Company." Please help me out what best I can do.