Samsung Galaxy S2 Sim Card memory full?

[zyclonenuz]

Hello everyone. My sister recently gave me her Samsung Galaxy S2 (4.0.4) anyway I keep getting this "sim card memory full" or something like that notification every 1 hour or every 2 hours. When I check sim card message it was empty. Also checked Sim card contact is empty.

anyone else had this problem ? is there a way to turn of that notification ?

thanks in advance.

sorry for my English.