I don't know what's going on....i hope someone can help me

Did you consider looking at line 39 of SFTP.pm to see where the error came from? This process is called UTSL amongst other things. Of course before resorting to RTFS you would typically RTFM which you will find at Net::SFTP. When you consult the documentation you may note that the module author has tried to help you..... For a start you could try turning on debugging:

$ssh = Net::SFTP->new($host, debug => 1 ) or die "Blech\n";
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which would further explain your 'Permission Denied' error. But if you do either of RTFM/RTFS you will note that you need to pass the USERNAME and PASSWORD to the new() constructor. This should work:

$ssh = Net::SFTP->new($host, user => $user, pass => $pass, debug => 1 
+) or die "Blech\n";
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