Google Analytics Fix

My website is currently running with Google Analytics code, but there's a problem - I'm missing vital revenue figures! I need someone with experience troubleshooting and diagnosing Google Analytics to find and fix the issue. I already have code installed on the website so the fix only needs to be made to the existing code - no new implementation required. Solving this issue is of utmost importance to me, so I'm looking for someone who can do a great job quickly!