Then you should write a formal letter to the Landlord.
The address should be on the contract.
They are OBLIGED to inform the Landlord.
In law you are liable for the whole term unless you are released early.
Usually, you would have to pay any re-letting fees and charges, plus rent for the empty period.
But they are required to give the Landlord your letter.
If they refuse then you can go to the Ombudsman:
Ask them who their professional body is and make a complaint to them.
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