I so much appreciate all the advice so far. I've been working on transferring the seems much important tokens to a new wallet address. Thanks to everyone for helping out.
that's better thing you can do if you know that your wallet is possible hacked because of that unknown transaction . Make that wallet empty and don't use that wallet any more , I don't have any idea if how secure IM token is but its better to sustain wallet like myether and meta mask for creating a wallet.