After you make a power of attorney, you can revoke it at any time. There are a variety of situations that would require you to do so. For example, the person named in your power of attorney is no longer able to serve. Your name has changed because of marriage or divorce. You lost the document or have moved to another state.
There are two ways to revoke your power of attorney. Prepare and sign a document called Notice of Revocation or destroy all existing copies of the document. The first method is preferable, because it creates proof that you really revoked the power of attorney.
The next step is to notify the former attorney-in-fact and all the institutions and people who have dealt or might deal with the former attorney-in-fact. This might include places like banks, Social Security offices, insurance companies and pension fund administrators.
In summary, once you create a power of attorney, the legal burden is on you to be sure everyone knows you have revoked it.