a. receive all written offers and counteroffers,
b. reduce offers or counteroffers to a written form upon request of any party to a transaction, and
c. present timely all written offers and counteroffers;
Offers must be presented EVEN IF THE PROPERTY IS UNDER CONTRACT. The rules don't say that present offers UNLESS the property is under contract.
If a better offer comes in after the house is under contract and the first contract falls out due to the appraisal not being ordered or inspections exceeding the repair cap, the contract can be cancelled by the seller and the new offer accepted.
I know of instances where a seller paid a buyer (buyer 1) to cancel their contract, so seller could accept an offer from another buyer (buyer 2).
I hope this helps. If you need an agent to stand up for you, let us know. Have a great day!