I'm left to suspect the wifi router or the settings.
Your post tells a little about the iphone, but not the hotspot.
Yeah, I have a iphone 3g that dont want to connect to my wifi...It's been doing great. It just started doing it all of a sudden. Here are some things I've tried...Hard/soft reset..erase all data n settings n reset network settings...I dont know what else to do to fix it..if you have an idea let me know plz.