PHP oci_connect: ORA-01017: invalid username/password; logon denied

Symptom:

In browser, user click button to search Oracle Database by the username typed in input field. It works once, then complain:ORA-01017: invalid username/password; logon denied , click again it works, if click again, it pops up the error message again.

What I did:

1. Double quoted the connection password (in wallet in my case.)
2. creating a file called "20-oci8.ini" in directory "/etc/php.d" with the following content.

; Enable oci8 extension module

extension=oci8.so

3. Disable the extension=oci8.so in /etc/php.ini