Then most likely a local networking issue… However, that is also the hardest, if even possible, for us to troubleshoot.
You need to set both code command and reprogram the ESP (with AT commands) when changing BAUD rates… but if as you state it did work elsewhere for extended times then leave it as is for now.
Can you layout your connection details… this looks a lot like your ESP is linking to a mobile hotspot or something, not your home router.
Also, how are you getting the Serial output?? via the programming USB port on the UNO? What is your ESP connection? Can you supply your code (properly formatted as shown in the Welcome Topic) so we can see.
You have a few years on me 
and I am also starting to yell “Get off my LAN!” as time goes on 
But good on ya for tackling a “current” tech trend 