SQL & PL/SQL

Hello,

I am trying to use replace function inside a Decode Function,

Here is how I am doing it:

select
SUBSTR (
DECODE (
IH.DRVD_ALT_MAIL_ADDR_PRIM_FLAG,
'N',
REPLACE (
ih.subs_addr_1
|| ' '
|| ih.subs_addr_2
|| ' '
|| ih.subs_city
|| ','
|| ih.subs_state_code
|| ' '
|| ih.subs_zip_code,
' ',
' '
),
'Y',
REPLACE (
IH.PRINT_ALT_MAIL_ADDR_LINE_1
|| ' '
|| IH.PRINT_ALT_MAIL_ADDR_LINE_2
|| ' '
|| IH.PRINT_ALT_MAIL_ADDR_LINE_3
|| ' '
|| IH.PRINT_ALT_MAIL_ADDR_LINE_4
|| ' '
|| IH.PRINT_ALT_MAIL_ADDR_LINE_5
|| ' '
|| IH.PRINT_ALT_MAIL_ADDR_LINE_6,
' ',
' '
)
) 1,
50
)
address from x


Can anyone please tell me what am I doing wrong here, It always gives me an error about missing a right parenthesis.

Thanks in advance.