PL/SQL Error With Nested IF statements

PL/SQL Error With Nested IF statements

Apex 4.2
I have the following pl/sql code block below but whenever I run it in
APex, I keep getting the error:
ORA-06550: line 35, column 4: PLS-00103: Encountered the symbol ";" when
expecting one of the following: if
DECLARE
show_changes BOOLEAN;
l_exists INTEGER;
BEGIN
Select count(*) into l_exists
From dba_role_privs
where grantee = upper(:APP_USER) and
(granted_role = 'SURVEY_JOB_SUID' or granted_role = 'SURVEY_SUID');
IF l_exists = 0 THEN /* unauthorized */
IF :P32_SURVEY_JOB_REQUEST_ID IS NOT NULL AND (:P32_SUBMISSION_DATE IS
NULL AND :P32_LOCK_DATE IS NULL) THEN
show_changes := TRUE;
IF :P32_SURVEY_JOB_REQUEST_ID IS NOT NULL AND (:P32_SUBMISSION_DATE IS
NOT NULL AND :P32_LOCK_DATE IS NULL) THEN
show_changes := TRUE;
IF :P32_SURVEY_JOB_REQUEST_ID IS NOT NULL AND (:P32_SUBMISSION_DATE IS
NOT NULL AND :P32_LOCK_DATE IS NOT NULL) THEN
show_changes := FALSE;
END IF;
ELSE /* authorized */
IF :P32_SURVEY_JOB_REQUEST_ID IS NOT NULL AND (:P32_SUBMISSION_DATE IS
NULL AND :P32_LOCK_DATE IS NULL) THEN
show_changes := TRUE;
IF :P32_SURVEY_JOB_REQUEST_ID IS NOT NULL AND (:P32_SUBMISSION_DATE IS
NOT NULL AND :P32_LOCK_DATE IS NULL) THEN
show_changes := TRUE;
IF :P32_SURVEY_JOB_REQUEST_ID IS NOT NULL AND (:P32_SUBMISSION_DATE IS
NOT NULL AND :P32_LOCK_DATE IS NOT NULL) THEN
show_changes := TRUE;
END IF;
Return show_changes;
END;
I'm not sure what the problem is. Any help would be greatly appreciated.
Thanks in advance.