Hi. If you inserted the SIM cards while the table was on, restart it. If that does not resolve the issue and you bought it new, then the SIM card's electro-mechanism may have failed in part. If it is just one SIM, then try a different SIM to be sure your Vodacom SIM is not damaged. If you bought the Verssed Motion E1.1 as a second hand, then it may have been blacklisted after being reported lost or stolen.