If you still want to cancel your contract, ask your listing agent or the office broker of record to cancel your agreement. Keep in mind, unless you are unconditionally released, you may still be responsible for a sales commission to your listing broker. This is to avoid sellers gaining marketing exposure for their home, but then canceling the contract once a buyer is in the picture.
All the best!
There should be instructions stated in the contract as to how to cancel. Most of the time you can just call the Realtor and/or Brokerage to ask, and that gets it done once the cancellation is signed. Be cautious of cancellation and/or retainer fees that may be charged to you... they do appear in some contracts and are due at cancellation of the agreement by the seller.
If they refuse to cancel, the good news is that December will soon be here.
Good luck to you,
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