Welcome to Android Central! What do you mean that the skipped messages remain indefinitely, and now you have no messages? Do you mean that you think they're supposed to remain indefinitely? Most carrier voicemail systems won't keep messages forever -- they'll get cleared out eventually (I think even if you save the messages). In any case, as Galactic Zoo mentioned, you'll need to contact your carrier about this. Voicemail is controlled by the carrier, not your phone.