Try reading the help page and FAQ for the product first.
Also try searching this site using the search field at top right.
To vote for or create new feature requests go here: Feature requests
FolderSync: Help, FAQ, Known issues
Otherwise you could try to use the forum to make your issue known or put forward your request. It has a separate search function - please use it first. We will answer you in there as quickly as possible. Then everyone will also have the benefit of seeing the answer.
If you want to report a specific problem with an app, then please include a log file using the procedure below.
How to create and send a log file