Overtime Enroll() program with fingerprint scanner

Good evening all !

I am having an issue with my fingerprint scanner Enroll() program.

I want to run it during a certain amount of time but I can't manage to make it work.
To be clear i want to run the program and if the fingerprint scanner is not pressed during 10sec, then the loop restarts.

Here is my code. can somebody help ??
Thanks a lot !

#include "FPS_GT511C3.h"
#include "SoftwareSerial.h"
FPS_GT511C3 fps(2, 3);

void setup()
{
}

void Enroll()
{
unsigned long exiTime = 0;
exiT=millis();
while(exiTime<=10000){
// Enroll test
Serial.begin(9600);
delay(100);
fps.Open();
fps.SetLED(true);

// find open enroll id
int enrollid = 0;
bool usedid = true;
while (usedid == true)
{
usedid = fps.CheckEnrolled(enrollid);
if (usedid==true) enrollid++;
}
fps.EnrollStart(enrollid);

// enroll
Serial.print(exiT);
Serial.print("Press finger to Enroll #");
Serial.println(enrollid);
exiT=millis();
while(fps.IsPressFinger() == false) delay(100);
bool bret = fps.CaptureFinger(true);
int iret = 0;
Serial.print(exiT);
if (bret != false && exiT<10000)
{
Serial.println("Remove finger");
fps.Enroll1();
while(fps.IsPressFinger() == true) delay(100);
Serial.println("Press same finger again");
while(fps.IsPressFinger() == false) delay(100);
bret = fps.CaptureFinger(true);
if (bret != false && exiT<20000)
{
Serial.println("Remove finger");
fps.Enroll2();
while(fps.IsPressFinger() == true) delay(100);
Serial.println("Press same finger yet again");
while(fps.IsPressFinger() == false) delay(100);
bret = fps.CaptureFinger(true);
if (bret != false && exiT<30000)
{
Serial.println("Remove finger");
iret = fps.Enroll3();
if (iret == 0)
{
Serial.println("Enrolling Successfull");
}
else
{
Serial.print("Enrolling Failed with error code:");
Serial.println(iret);
}
}
else Serial.println("Failed to capture third finger");
}
else Serial.println("Failed to capture second finger");
}
else Serial.println("Failed to capture first finger");
}
Serial.print("out");
}

void loop()
{
Enroll();
delay(1000);
}