Changing information to a diffierent account after bank reconciliation

Good morning,

I have a question that I would like some input on. This is the first year that our not for profit is using quickbooks online. When setting up the accounts, I created a sub accout to keep track of transaction fees pertaining to each event we have. This has become quite onerous and probably unnecessary and I would like to remove each transaction account and add them to a main account. I have set up the main account and changed one month however as the account is reconciled the first week of the following month, my reconciliation reports are now incorrect. I'm not sure if the account is now out of balance. Can I re-run the monthly reconciliation report and how can I do this for each month separately. I tried redoing the reconciliation report by selecting the monthly date but the balance that shows is the total to the current date. Any suggestions please.