Reconciling a Credit Card Account

I have several Credit Card accounts. When I reconcile them a window pops up asking for the relevant information for the statement I am reconciling. With one of them (a new one) that window does not pop up. I suspect that somehow it went on Auto Reconcile since it was showing transactions reconciled that I had not reconciled. I started to delete the auto reconciled transactions (probably shouldn't have done that). I can't seem top find the auto reconcile button to turn it off. How can I switch back to manual reconcile (statement by statement) and undo any "damage" I did by "unchecking" auto reconciled transactions. Thanks for your help