My Phone has been locked once I changed SIM Card

Hi,

I have Samsung Galaxy Plus I9001 Android mobile and I have installed Avast Anti-theft(NON-ROOT). Just I removed(and again I inserted SIM) my SIM card yesterday from that time it is started giving SIREN. I know the avast password even though it is not unlocked, I tried with SMS commands also, but no luck .
Please suggest on the same.
Thanks in advance…

Open avast! and set the card (SIM) as a trust one into the antitheft settings. I think it’s something like “Clean SIM list”.

yeah its in the options menu.