Company not allowing early release

Hi I am requesting for my current employer for an early release on 26th May 2023 and I have applied my resignation on 24th March 2023 which my offer letter stated for 90 days notice period. I got better opportunity role in other organization and having better hike with having option WFH. Below if my company Notice period policy "Your employment with the Company can also be terminated either by the Company or by you by giving the other party 90days advance notice. If the Company terminates the employment and decides to relieve you before the completion of the notice period, the “Basic” component of the salary for the balance notice period would be paid to you. If at your request, the Company agrees to relieve you before serving the full notice period, you will be liable to pay the Company the “Basic” component of the salary for the balance notice period. However, please note that accepting any such early relieving request would be entirely at the discretion of the Company. On termination of your employment for any reason, you shall comply with the Company’s termination procedures, sign all documents and return all Company property. The Company will not be bound to pay the dues, if any, till you have completed all the separation procedures." The current employer Manager and HR and informing has we cant able to relieve soon has we dont have manpower its difficult to relieve soon. But I have informed that Its not my role looking for other manpower in my place and has per policy I am ready to pay balance notice period but they are not accepting stating we dont have manpower. I basically work on Client company with Payroll from HCL Technology. Where Client made terminate 4 people because of some reasons and with all this now the HCL Technology stating me that due to very less manpower its difficult to relieve me soon. Required support what can be done in such case so that I can get relieve soon and start my better growth in new organization.