wifi password

Sorry, not a question. But maybe will help another novice like me.

For a couple years now I've daily used my Ipad with wifi in my small house. Signal from modem(I thought) has always been fine. But for over a year, my Iphone received no signal. Procrastinated in troubleshooting, until my Ipad wifi signal disappeared the other day.

Finally talked with Xfinity agent, and realized that I had never entered my password for a network name on the modem. The Ipad had picked up a signal floating around the neighborhood. 

Found the password written in my address book, entered it, and all devices receiving strong wifi signals now. Oh well.