I hope you are well today and thank you for your question.
Please don’t share sensitive information on the forum as this is public forum so the information shared can be misused by others.
Please change the shared credentials ASAP.
If you want to share anything privately then you can do so by adding them in the box having text “Enter your private content here (only you and forum moderators will be able see it)”.
The error is occurring because the js_composer folder already exists in the /wp-content/plugins/ directory of your WordPress install so please remove the js_composer directory by accessing your site using FTP or cPanel file manager.