Have just installed this in http://www.irishshopper.com but when I try to access the test file (testfile.php) I receive these error messages

Fatal error: Uncaught exception 'TwitterException' with message 'Status is a duplicate.' in /home2/irishisb/public_html/isa38/twitter/twitter.php:204 Stack trace: #0 /home2/irishisb/public_html/isa38/twitter/twitter.php(648): Twitter->doCall('statuses/update...', Array, true) #1 /home2/irishisb/public_html/isa38/twitter/testfile.php(21): Twitter->updateStatus('New Product Ava...') #2 {main} thrown in /home2/irishisb/public_html/isa38/twitter/twitter.php on line 204