I do need a sketch to turn on a relay only for 5 seconds and then turn permanently off using esp8266 and blynk app without using the timer widget in blynk app.
Since we do not write code on demand here… What is your question?
If what commands to use… try BlynkTimer and a timeout timer
Please learn to use the SEARCH function. This was just covered the other day, except using 10 seconds. Try looking around for an answer instead of asking others to do it for you.
There are many examples on there that cover it.