4GL needs to know how many lines of space will be devoted to page headers and trailers; otherwise, it does not know how many detail rows to allow on a page. Since it cannot predict how many times a loop will be executed, or which branch of a CASE will be execute, it forbids the use of PRINT in these contexts within FIRST PAGE HEADER, PAGE HEADER, and PAGE TRAILER sections. You have to rearrange the code to place the PRINT statement where it will always be executed.