The reason you are receiving this message is because we have a minimum value on the amount of free RAM/disk space that must be available on the phone memory before Vlingo will allow you to issue a command. Furthermore, the amount of available space on your phone memory is probably too low for Vlingo to perform a recognition. We have set the software to not allow voice recognition when the phone memory is under 10MB, regardless of how much memory is on your memory card. With that said, please free up some space on your phone, either by deleting unused files or transferring memory to your phone's memory card.
Please note that 10MB of free memory on the phone is really pushing the phone to the limit and, subsequently, space must be freed up in order to avoid problems with applications on the phone. This is especially true with Vlingo, which uses some memory when it is processing a spoken command.