Glad I use an alternative phone number, pinger, for two factor forced by phone services.
Facebook in this case, I have it set to authenticate by accepting it through another location I'm signed into. Such as from my phone (I use Friendly, instead of facebook's app), or a computer I've already signed into. As long as I have access to one location I'm signed into, and that isn't very many, I'm good.
Though, I usually have to re-authenticate every month when I decide to check it, followed by reminding the people I care about, who has messaged me, to contact me by phone or text.