Connection lost with my device

Hello everybody.
I’m facing an issue with my project (an led neon sign controlled by an esp8266). This project was working perfectly fine for a year, but for some reason it just stopped working. Precisely my esp8266 can’t connect to my wifi network. I uploaded a code with the Blynk Edgent ESP8266 exemple but there is an error when uploading the code. Can somebody explain me why my device just don’t want to connect to my wifi ?

Do you really expect people to be able to answer that based on the almost non-existent information you’ve provided?

I’d start by providing ALL of this information as a minimum…

Pete.