PHP validation not working

[sols4comp]

I have created a php form that connects to a MySQL database. This is working fine however I have added validation and this doesn't appear to be working correctly and still posts to the results to the database regardless of if they are validated or not. Any ideas?

[sols4comp]

<?php
// define variables and set to empty values
$nameErr = $lnameErr = $ageErr = "";
$name = $lname = $age = "";
if ($_SERVER["REQUEST_METHOD"] == "POST") {
 if (empty($_POST["name"])) {
     $nameErr = "Name is required";
      } else {
$name = test_input($_POST["name"]);
   // check if name only contains letters and whitespace
if (!preg_match("/^[a-zA-Z ]*$/",$name)) {
  $nameErr = "Only letters and white space allowed";
    }
  }
if (empty($_POST["lname"])) {
$lnameErr = "Last Name is required";
  } else {
$lname = test_input($_POST["lname"]);
  }
  if (empty($_POST["age"])) {
$age = "";
  } else {
$age = test_input($_POST["age"]);
  }

  }
?>

[Dani]

So sorry for the delay in replying to this. Can you show us the code for test_input()? Is that the function you're saying is failing? What input are you entering and what error are you expecting to see?