Most home phones are sophisticated enough to hold many voicemails. However, because phones do not have an infinite memory, it is necessary to regularly delete older messages in the phone. While this varies somewhat from phone to phone, there are general means by which phone messages can be deleted. By doing this, it is possible to free up memory and ensure that all new messages are able to be saved, and none are missed.
Call your voicemail, either remotely from another phone, or from your own phone. If you have an answering machine, press "Delete" when reviewing old messages.
Dial your password when required. If no password is required, press the number (usually 1) that corresponds to playing old messages.
Delete old messages you do not wish to keep. As the old messages are played back, press the button that deletes them: It may vary from company to company. If you are unsure, listen to the automated response when the number is pressed. If "Message Deleted" is the response, then this is the correct number.
Continue deleting all unwanted messages until the inbox is clear. This will now leave space for incoming messages.