Based on your ORIGINAL question...here is the answer from RingCentral support articles. You later bring up about short codes, however this is the answer to your original question.
Checking voicemails over the phone
You can check your voicemails using your mobile phone or landline phone (non-RingCentral phone) by following the steps below.NOTE: If you prefer to check your voicemails using your IP phone, see RingCentral Phones Function Keys: * and # Codes for more information.
1. Call your RingCentral Main Number or Direct Number.
2. Enter your extension number as soon as you hear the ring. If you are calling your Direct Number, go to Step 3.
3. Press the star key (*).NOTE: If you do not have a greeting in your extension, press the star key after the 2nd ring.
4. Enter your PIN followed by the hash sign (#) once prompted.
5. Listen to the prompt for instructions or press One (1) to listen to your messages. For the list of commands, go to Options when listening to a voice message over the phone.
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