Ad redirect to spam

Technical Details

Forum version : #phpBB3
Position : Administrator
Concerned browser(s) : Google Chrome, Internet Explorer
Who the problem concerns : All members
When the problem appeared : Since creation of the forum (a few weeks ago)
Forum link : http://creativewritingclub.forumotion.com

Description of problem

I am a high school teacher with a writing club of students who want to work through this forum we created. However, the site is redirecting to spam/hacker websites that could be potentially harmful. I myself have had this happen on my Android phone (using Chrome) and my home desktop computer (using Edge and Chrome). I don't have a screenshot, and it doesn't happen to me every time, but it usually happens when I log in. Underneath the spam page is the regular site where I am now logged in, but I won't be able to reach it until I can get rid of the redirect spam site that is asking me to call a number and give them all of my information (to steal). These are high school kids, and I don't them exposed to this, and some of them can't even get past it enough to create an account. This is obviously an advertiser who has done a bait-and-switch, so I know it's not your site, but it is redirecting from your advertiser. What can be done? I hate to delete all of these accounts and create a whole new forum just because of this, but it's ridiculous and annoying, not to mention a dangerous scam, especially to kids. Thanks for any help you can give.

Thank you for the response. I did not post there originally because it seemed to just be a bunch of people complaining about the issue with no one actually solving it or getting to the bottom of the issue. I have now reposted as a reply there, so we shall see. Thanks!