Parse error: syntax error, unexpected '<', expecting end of file in sitemap#xml on line 3

Fatal error: Uncaught Error: Call to a member function main() on null in /home/humanizzare/www/wp-includes/functions.php:1336 Stack trace: #0 /home/humanizzare/www/wp-blog-header.php(16): wp() #1 /home/humanizzare/www/index.php(17): require('/home/humanizza...') #2 {main} thrown in /home/humanizzare/www/wp-includes/functions.php on line 1336