You are unable to move a Misc Account to Operating. Making this change has the potential to cause the Balance Sheet to be out of balance along with other errors.
You will need to create this bank account up as an Operating type account, then enter any outstanding transactions into that Account using a balance sheet type/clearing account.
Once completed, the outstanding items can be adjusted off in the Misc. Account to the same chart of account (balance sheet or clearing type account) in order for the account to be set to zero.
Once zero, you can make this account Inactive from within the Administration / Accounts Management / Hotel Account / Miscellaneous Accounts.