The Permission denied error occurs when permissions for a file/folder are incorrectly set
To solve this problem you need to change the permissions for this or that object.
To do this, go to "Files → File Manager"
You can learn more about File Manager functions here
Select the desired item. Highlight it and click "Permissions"
Set the rights to 755
Now you can delete a file or folder.
Info
If you have any difficulties or need help, please create a support request via ticket system and we will be happy to help you.