you can try the following steps to troubleshoot the issue:
Check the chatbot's configuration settings in Pega. Make sure that the chatbot's response message for case resolution is configured correctly and is not mistakenly set to "Thank you for your input". If it is set incorrectly, update the configuration to the appropriate response message.
Check the post-processing configuration of the case type that the chatbot is handling. Ensure that the post-processing configuration is set up correctly and is not sending the "Thank you for your input" message as a response to case resolution.
Check if there are any automation or decision rules that are executed when a case is resolved. Ensure that these rules are not configured to send the "Thank you for your input" message as a response to case resolution.
Review the logs and chatbot transcripts to identify any patterns or potential triggers for the issue.