its too bad, barely two weeks ago, there was still a way to get the old ironfall back.
but for now, download the most recent homebrew starter pack
https://smealum.github.io/ninjhax2/starter.zip
copy the contents to your sd (since you had homebrew running already, i assume you know what goes to root and what to the 3ds folder) and overwrite whatever old files you still have
then go to your browser, delete bookmarks and cookies. turn off wifi and look for the option that basically resets the browser (initialize i think?)
start the browser again, click through the help messages and set a search machine, then exit browser.
turn wifi back on, hit L+R to start camera, scan for qr code on this page
and it should send you right to homebrew loader. from there, look for menuhax manager 2.1, install that (it will reset your theme, but you can set one of the basic color themes afterwards) and now, you can enter homebrewloader by holding L button while powering on your 3ds.
dont change themes from the homemenu though, since that removes menuhax again