I submitted "daily", rather than "every day", but my answer was not accepted--is there a reason for this, or is it a DL error?
It probably wasn’t anticipated by the course creators as being an acceptable translation for gach lá. (“Quotidianly” probably isn’t accepted, either.)
The adverb phrasing, ie to approximate "daily ", might be different in Irish. It might include a variant of "o' la' go la'".