BE CAREFUL, don't put your memo key on memos, otherwise anyone could read your (not anymore) private messages on wallet (memos). I don't know if on some exchanges it is required.

On binance was a fault for me to set my memo key on MEMO field.

To fix it, you should change your master/backup password to change all your keys. Please, upvote so this can be seen by others.
I would like to thank @noblebot for his/her kind warning.