Unable to Get Validators for File_Save_Upload to Process

I've been trying to get validators for a file_save_upload call to work without much luck. Here's the code I'm working with:

<?php

function wwguser_edit(){
	
$form['report_logo'] = array('#type' => 'file',);

$form['submit'] = array(
		'#type' => 'submit',
		'#value' => t('Save'),
		);	

}

function wwguser_edit_submit($form, &$form_state) {
		
		$validators = array( 
			'file_validate_extensions' => array( 'jpg jpeg' ),
			'file_validate_image_resolution' => array( '160x70' ),
			'file_validate_size' => array(50*1024, 0),
		);

		if ($file = file_save_upload('report_logo', $validators, file_directory_path())) {
			file_set_status($file, FILE_STATUS_PERMANENT);
		}

}

?>

Using the above code I'm able to upload files without issue to the correct directory and entries are created in the {files} table with a status of 1 (permanent). However, my validators aren't processed at all so I'm allowed to upload any kind of file I choose at any file size. The only thing I've been able to get to work is swapping the "file_validate_extensions" for a "file_validate_is_image". Using that validator works as expected (an error is thrown if I select a .txt file for example) but my size and resolution validators still aren't processed. I'm assuming it's a syntax error as the "file_validate_is_image" works fine and the file uploads correctly.

Can anyone help me out with this?

Thanks.