The instructions call for the Answer to be served by mail (or hand delivered) by somebody other than the Defendant and the Affidavit of Service must be notarized.
"You are responsible for arranging to have the Answer served but you must get someone else to do the service. Anyone over the age of 18 who is not involved in the lawsuit can serve the papers by mail or by personal service (hand delivered). You can ask a friend to serve the papers, or hire the Sheriff or a private process server."
"A copy of your Answer is placed in an envelope addressed to the Plaintiff’s attorney (or the Plaintiff, if there is no attorney) with your return address on the envelope and is then sent by First-Class Mail. The server must drop the letter in the mailbox or give it to the postal worker."
"After the Answer is hand delivered or mailed, the person who did the service must fill out an Affidavit of Service form and sign in front of a notary."
While a private process server is optional, the OP has certainly screwed up the service by not having a notarized affidavit and, you're right, the OP needs to have it served all over again and make sure the server provided a notarized affidavit of service.
Getting another amateur to serve the Answer risks getting it screwed up all over again. But that's up to the OP.