Buying Fix PHP header error - Quick & Easy Fix

I have a problem with my php file on my site that should redirect to a certain page when 'x' = a value.

For instance, you can see the error here:

http://hop.clickbank.net/?copyprofit/loot4leads&x=volume1


Please let me know if you can help as I'd expect it's just a simple fix.

 

I Think i can take up this task and can start now will charge only 5$

 

put ob_start(); as the first line of code in that page.