1. You shall have to give three months notice or pay three month's salary in lieu there of,
2. Since you could not give three month's notice, have you refunded/paid three month's salary in lieu of the notice period alongwith with your resiagnation letter?
3. If not, you should immediate issue them a cheque to that effect,
4. After that you can claim the relieving letter from your employer,
5. You can also join the new organisation if they allow you to join without releiving letter,
6. You can claim the relieving letter later on if you have resigned properly as per the terms laid down in your appointment letter or service conduct rule of your present company.