Invalid function

I am getting a compile error staing Invalid Function Name for INTERGER-OF-DATE and UPPER-CASE. They are valid according to the documentation. What is wrong with the code below?

MOVE FUNCTION INTEGER-OF-DATE(WK-DATE-INTEGER)
                         TO      WK-REPORT-ANIC-DATE-INTEGER.

Move FUNCTION UPPER-CASE (PMLink-In-Payee-Name)
                To NPAY-NAME

Thanks