There are several types of notarial certificates. If your document doesn’t have one you need to select which type, you need.
The first type is acknowledgment. I’ll go over it here.
An acknowledgement is a declaration by a person who signs a document in front of a notary public. The person states that they signed the document voluntarily and for the purpose stated in the document.
This also means that this person is aware that they are signing the document or documents under their own free will and are not being forced to otherwise.
