Not to worry. It happens with the best of us. There may be situations where the wrong account is an income statement one, the balance sheet one or even both. No matter the situation, it’s remedied.

First things first, you have to undo the initial entry by taking it back (by decreasing the payable you booked and taking also back the expense you charged):

Db Payable / Liability account
Cr Expense account

And then after you’ve made sure the accounts are correct this time, make the entry once more, but a correct one this time:

Db Expense account
Cr Payable / Liability account

With this you’ve now charged the expense onto the right account and booked the payable for it just as well.

Accounting entries made onto wrong accounts happen and there’s nothing to be worried about. As long as you discover the mistake within short time period you can remedy it still within the same reporting period. Mind you that if it’s within the reporting period you do not need to go back to make amendments, but you can simply make the adjustment in the current month. There may be possible tax implications, but that’s something you should consult your local legislation about.