You should read this…
However, when you’ve made that change you sketch won’t work as I suspect you are hoping it will.
void setup only executes once, so the IR sensor will be read just once - when the device boots. In addition, placing a Blynk.virtualWrite in void setup almost certainly won’t write the data to Blynk because although Blynk.begin() has executed Blynk.connected() is not yet true.
And, don’t be tempted to place the IR code that’s currently in void setup into the void loop, this breaks the #1 rule of Blynk.
Instead, you need to set-up a BlynkTimer to call a function on a regular basis and put your IR code in there.
I’m also a bit confused about why this is an IR sensor. If you’re attempting to figure out if a vehicle is parked in a space then why not use a simple LDR, Photodiode or luminance sensor?
Pete.