ExecuteStatement() and ExecuteScalar() with Linked Table

i created a linked table , in my business logic , row inserting server event , i used thes queries



  //remote
$studentportal = ExecuteStatement("INSERT INTO fabotasp_studentportal.users (name,firstname, othername,Matricno,examnobackup,password,status,dpt,dptcode,userlevel)
 VALUES ('$name', '$firstname', '$othername','$email','$examnobackup','$password','$status','$dpt','$dptcode',1)");

  // get userid on collegeportal.users tbl
  $getuserid = ExecuteScalar("SELECT id FROM fabotasp_studentportal.users  WHERE 	Matricno='$examnobackup'");

  // create data in collegeportal.studentlevel
  $studentlevel = ExecuteStatement("INSERT INTO fabotasp_studentportal.studentlevel (student_id, level,portalsession) 
  VALUES ('$getuserid', '$level', '2022/2023')");

this works well on local but when i move to remote i get

INSERT command denied to user ‘fabotasp_acctance2’@‘localhost’ for table ‘users’

alternativly i use direct mysqli() in sever event but i got error class mysqli not found. i=how do i use this ? i KNOW ITS NOT RECOMENDED BUT THIS IS A QUICK FIX FOR ME

 // insert into student portal  

$servername = "localhost";
		$username = "sportal";
		$password = "*******";     
		$dbname = "fabotasp_studentportal";

		// Create connection
		$conn = new mysqli($servername, $username, $password, $dbname);

		$sql = "INSERT INTO users (name,firstname, othername,Matricno,examnobackup,password,status,dpt,dptcode,userlevel)
     VALUES ('$name', '$firstname', '$othername','$email','$examnobackup','$password','$status','$dpt','$dptcode',1)";
		if ($conn->query($sql) === TRUE) {

		  //echo "New record created successfully";
		} else {

		 // echo "Error: " . $sql . "<br>" . $conn->error;
		}
	
	
	
$sql2 = "SELECT id FROM users  WHERE	Matricno='$examnobackup'";
$result2 = $conn->query($sql2);

if ($result2->num_rows > 0) {
  // output data of each row
  while($row = $result2->fetch_assoc()) {
  $getuserid =  $row["id"];
  echo $getuserid;
  }
} else {
  //echo $getuserid;
}

	
		$sql3 = "INSERT INTO studentlevel (student_id, level,portalsession) 
      VALUES ('$getuserid', '$level', '2022/2023')";
		if ($conn->query($sql3) === TRUE) {

		  //echo "New record created successfully";
		} else {

		 // echo "Error: " . $sql . "<br>" . $conn->error;
		}

https://discourse.hkvstore.com/t/dynamic-user-levels-and-linked-tables/6201/14