Try to test and initialize your arrays before you use them :
if( !isset($catagory[$i]) ) $catagory[$i] = '' ;
if( !isset($task[$i]) ) $task[$i] = '' ;
if( !isset($fullText[$i]) ) $fullText[$i] = '' ;
if( !isset($dueDate[$i]) ) $dueDate[$i] = '' ;
if( !isset($empId[$i]) ) $empId[$i] = '' ;
If $catagory[$i]
doesn't exist, you create (Uninitialized) one ... that's all ;
=> PHP try to read on your table in the address $i
, but at this address, there's nothing, this address doesn't exist => PHP return you a notice, and it put nothing to you string.
So you code is not very clean, it takes you some resources that down you server's performance (just a very little).
Take care about your MySQL tables default values
if( !isset($dueDate[$i]) ) $dueDate[$i] = '0000-00-00 00:00:00' ;
or
if( !isset($dueDate[$i]) ) $dueDate[$i] = 'NULL' ;