You can withdraw your proposal until you are offered a contract. After that, you’ll need to turn down the offer or end the contract. You are never obligated to accept a project you don’t want. You won’t be penalized by Upwork for withdrawing a proposal or declining an offer. To withdraw a proposal:

1. Click your Find Work tab, and then click Proposals.
2. In the Active tab, find the proposal you want and click the Withdraw link.
3. Select a Reason.