Unauthorized images downloaded onto our website including a disparaging comment

As administrator for the New Dimensions website I track all of our downloaded images.  However there are some new images that have been downloaded without my or the president's knowledge, including a highly disparaging comment at the bottom.  How do I find out how this was added, and how do I remove the disparaging comment.

Without your club number we cannot assist you.

Club #03022465

1) by download, you really mean upload to your site.

2) The site admin has control of the file manager and can allow 3 additional officers access. (You have Pres, VP ED and Secretary.)

3) Your home page is damaged and missing HTML elements and is showing the template accordion exploded.
3a) The main heading was corrupt. The main heading is intended to be 1 line of text. and no HTML.

Not sure what all that means in terms of “template accordion exploded”, but the unauthorized photos are now removed somehow, along with the disparaging comment. Not sure how to prevent that in the future.

Those images are part of the template.
What do you mean by " disparaging comment " ?

You can turn off the template in the "Default TM Information Panes on Homepage" in the Homepage appearance settings.