False Prophets, false ideas.
“Man” is Ellen Gould White (E. G. White)
Seventh-day Adventism is a sect of Christianity that believes, among other things, that worship services should be conducted on the “seventh day” (the Sabbath) instead of on Sunday.
Today, most Seventh-day Adventists still consider Ellen White to be a prophetess of God, even though many of her prophecies failed to come true.
https://www.gotquestions.org/Seventh-Day-Adventism.html