ترجمة - أندونيسي-انجليزي - ka.. ridwan. saya bel ko tdk nyambung tlng dibuka...

مكتوب قبل هذا رقم هاتف.

The source is very informal (conversational). "Kak Ridwan" can have at least three meanings (a.) if the caller is Ridwan's sister or brother, it should be translated into: "Brother Ridwan". (b.) if the caller is Ridwan's lover/spouse, it should be translated into" "My honey Ridwan". (c.) if the caller is Ridwan's friend, potentially younger colleague, it could be "Dear Ridwan".

Second point, it is unclear what is to open. I guess it is an e-mail.