1. If you're the one who posted about it being unavailable on wifi, please don't double-post.
2. If you have a fixed IP address in the phone, it has to be compatible with your router's address range. If not, the router may have no more addresses to lease (you can set the range in the router - if you set, say, 3 addresses as available, and there are 3 devices connected, you can't connect another one).