On Bonsai, a proposal's status is automatically updated. As such, there isn't a method to manually mark a proposal as declined.
However, you can manually mark a proposal as accepted. To learn more about this process, take a look at our article titled Can I mark my proposal as 'accepted' for my client?
Proposal statuses
To identify the status of a proposal, head over to your Proposals page by selecting Client Management > Proposals in the navigation bar.
Hover over the circular indicator to the left of the proposal entry to view its status.
Light grey - Drafted
Dark grey - Sent
Orange - Declined
Green - Accepted
If you require additional support, get in touch with Bonsai's Support team at support@hellobonsai.com.