PHP - Problem With Bind_param()

Call to a member function bind_param() on a non-object in /models/class.newuser.php on line 131

$stmt->bind_param("ssssi", $this->username, $secure_pass, $this->clean_email, $this->activation_token, $this->user_active);
$stmt->execute();
$inserted_id = $mysqli->insert_id;$stmt->close();
//Insert default permission into matches table
$stmt = $mysqli->prepare("INSERT INTO ".$db_table_prefix."user_permission_matches (
user_id,
permission_id
)
VALUES (
?,
'1'
)") ;


$stmt->bind_param("s", $inserted_id);
$stmt->execute();
$stmt->close();

<?php
/*
.
.
*/


class User 
{
	public $user_active = 0;
	private $clean_email;
	public $status = false;
	private $clean_password;
	private $username;
	public $sql_failure = false;
	public $mail_failure = false;
	public $email_taken = false;
	public $username_taken = false;
	public $activation_token = 0;
	public $success = NULL;
	
	function __construct($user,$pass,$email)
	{

		//Sanitize
		$this->clean_email = sanitize($email);
		$this->clean_password = trim($pass);
		$this->username = sanitize($user);
		
		if(usernameExists($this->username))
		{
			$this->username_taken = true;
		}
		else if(emailExists($this->clean_email))
		{
			$this->email_taken = true;
		}
		else
		{
			//No problems have been found.
			$this->status = true;
		}
	}
	
	public function userCakeAddUser()
	{
		global $mysqli,$emailActivation,$websiteUrl,$db_table_prefix;
		
		//Prevent this function being called if there were construction errors
		if($this->status)
		{
			//Construct a secure hash for the plain text password
			$secure_pass = generateHash($this->clean_password);
			
			//Construct a unique activation token
			$this->activation_token = generateActivationToken();
			
			//Do we need to send out an activation email?
			if($emailActivation == "true")
			{
				//User must activate their account first
				$this->user_active = 0;
				
				$mail = new userCakeMail();
				
				//Build the activation message
				$activation_message = lang("ACCOUNT_ACTIVATION_MESSAGE",array($websiteUrl,$this->activation_token));
				
				//Define more if you want to build larger structures
				$hooks = array(
					"searchStrs" => array("#ACTIVATION-MESSAGE","#ACTIVATION-KEY","#USERNAME#"),
					"subjectStrs" => array($activation_message,$this->activation_token,$this->username)
					);
				
				/* Build the template - Optional, you can just use the sendMail function 
				Instead to pass a message. */
				
				if(!$mail->newTemplateMsg("new-registration.txt",$hooks))
				{
					$this->mail_failure = true;
				}
				else
				{
					//Send the mail. Specify users email here and subject. 
					//SendMail can have a third parementer for message if you do not wish to build a template.
					
					if(!$mail->sendMail($this->clean_email,"New User"))
					{
						$this->mail_failure = true;
					}
				}
				$this->success = lang("ACCOUNT_REGISTRATION_COMPLETE_TYPE2");
			}
			else
			{
				//Instant account activation
				$this->user_active = 1;
				$this->success = lang("ACCOUNT_REGISTRATION_COMPLETE_TYPE1");
			}	
			
			
			if(!$this->mail_failure)
			{
				//Insert the user into the database providing no errors have been found.
				$stmt = $mysqli->prepare("INSERT INTO ".$db_table_prefix."users (
					user_name,
					password,
					email,
					activation_token,
					last_activation_request,
					lost_password_request, 
					active,
					title,
					sign_up_stamp,
					last_sign_in_stamp
					)
					VALUES (
					?,
					?,
					?,
					?,
					?,
					'".time()."',
					'0',
					?,
					'New Member',
					'".time()."',
					'0'
					)");
				
				$stmt->bind_param("ssssi", $this->username, $secure_pass, $this->clean_email, $this->activation_token, $this->user_active);
				$stmt->execute();
				$inserted_id = $mysqli->insert_id;
				$stmt->close();
				
				//Insert default permission into matches table
				$stmt = $mysqli->prepare("INSERT INTO ".$db_table_prefix."user_permission_matches  (
					user_id,
					permission_id
					)
					VALUES (
					?,
					'1'
					)") ;
					
					
				$stmt->bind_param("s", $inserted_id);
				$stmt->execute();
				$stmt->close();
			}
		}
	}
}

?>

I'm new to coding and prepared statements.

I'm getting:
"Fatal error: Call to a member function bind_param() on a non-object in /home/content/01/3251001/html/Manage-Users/acc-files/updateRecord.php on line 17"

For this:

 <?php

include "db_connect.php"; 

if(isset($_POST['UserID'])){
	
	$stmt = $con -> prepare('UPDATE UserList 
		SET Status = ?,
			FirstName = ?,
			LastName = ?,
			Username = ?,
			Email = ?,
			Department = ?,
			Manager = ?,
		WHERE UserID = ?');

	$stmt -> bind_param('isssssss', /* Line 17 */
		$_POST['Status'],
		$_POST['FirstName'],
		$_POST['LastName'],
		$_POST['Username'],
		$_POST['Email'],
		$_POST['Department'],
		$_POST['Manager'],
		$_POST['UserID']);
	
	$stmt->execute();
}

Thank you in advance for helping.

2 9 0 1

Fatal error: Call to a member function bind_param() on boolean.

It fails on the BIND_PARAM line.

I have looked at this all day, struggling with Mysqli as my normal MySql works fine with assoc and fetch.

I have verified in PhpInfo that mysqli is enabled.

I have verified its loaded using <?php print_r(get_loaded_extensions());

Added utf8 just to make sure. 

If I manually use the Wrong Password, I get a connection refused error, so I know its connected.

Verified my $_POST variables are there using Print in the 2 9 0 1 above.

All Table and Field Names are correct.  Manual Insert works fine in myPhpAdmin.

Tried Field Names and ? marks with and without single quotes.

All fields are Integers in the table.

Could it be related to an Auto_Increment Field in the table for a record ID that I am not providing??

A normal insert in myPhpAdmin doesn't need it.

        $QuestionID = $_POST['qID'];
        $PlayerID = $_POST['pID'];        
        $Answer = $_POST['ans'];
        $Option = $_POST['opt'];
        

        print $QuestionID . " ";
        print $PlayerID . " ";
        print $Answer . " ";
        print $Option . " ";

        $database = "Survey";

        $db_found = new mysqli('localhost', 'survey', 'survey', $database);
        $db_found->set_charset("utf8");
        
        if (!$db_found) {
            echo "Error: db connection = false";
        }
        else {
            $SQL_INSERT = "INSERT INTO 'Answers' ('QuestionID', 'PlayerID', 'Answer', 'Option') VALUES (?,?,?,?)";
            $stmt = $db_found->prepare($SQL_INSERT);
            $stmt->bind_param('iiii', $QuestionID, $PlayerID, $Answer, $Option);
            $stmt->execute();
        }

Thanks,

CadJoe

public function Update(Entry $e)
    {
        try
        {
            $query = "update entry set string = $e->string,delimiter=$e->delimiter where entryid= $e->id";
            $stmt = $this->db->mysqli->prepare($query);
            $stmt->bind_param('ssi',$e->string,$e->delimiter,$e->id);

            $stmt->close();
           

        }
        catch(Exception $ex)
        {
            print 'Error: ' .$ex->getMessage();
        }
    }