Why can't I run the execv() syscall?

Question

I can't run execv(), when I build the code it fails.

This is my main.c:

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main(int argc, char *argv[])
{
char *args [] = {"Hello", "NESO", "Academy", NULL};
    execv("./dotask",args);
printf("this is main.c");
return 0;
}

And this is my dotask.c:

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main(int argc, char *argv[]){

printf("we are in dotask.c");
return 0;
}

I want to run the main.c and put char *args into dotask.c with execv() and see printf("we are in dotask.c");, but it fails. Anyone got idea what is the problem with it?