Is it true that even if an account is balanced it does not mean that it is correct?

Yes!
Even if an account is balanced, that is not to say that everything about the account is correct. Although the principle of accounting equation makes us understand that at all times, the balance sheet must balance. And that this demonstrates the accounting equation of
Assets = Capital + Liabilities.
But do not forget that there are errors that do not affect the agreement or balancing of the trial balance. This is true as there are some errors that do not affect the agreement of a trial balance. Thus, whenever any of these errors is made, the trial balance will still balance. For this, it is correct to say that even if an account is balanced, it does not mean that it is correct.

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