Sim swop

<p>My cell phone was ****** about a year ago. I cant be sure... i decided to use another network. I now want to go back to vodacom and support them, however they can not change or do a sim swop because i cant remeber the last amount of airtime or what phone i used! how would i remember that type of information after a year???? i think i would rather use another network and support them in future. </p>