When using a wireless phone that uses a SIM card, the messages you receive, both voice and text, are often stored on the card. This can take up a large amount of memory space on the card and prevent you from adding additional information to your SIM card, including other contact numbers, or receiving new text messages. To make room, you need to delete the current messages on your phone.
Power on your phone and select "Voicemail." Most phones keep the voicemails on a server that you dial in to; however, some phones store the actual message on the SIM card.
Select the message you want to remove and press "Delete." When asked if you want to remove the message, select "OK." Repeat the process with all of the messages you want to repeat.
Close out the voicemail options menu and select "Text Messages." This brings up all of the conversations you have had with individuals via text message.
Select a conversation you no longer want and press the "Delete" button. Again, a message appears, asking if you are sure you want to remove the conversation. Select "Yes" and the message is removed.