Alabama Code Title 35. Property § 35-10-23

All notices or demands to enter partial payments or satisfaction of balance of debt secured as is provided in Section 35-10-21 shall be in writing and signed by the party or parties who are entitled to have the entries of record made, or by their personal representative, or by their agents duly authorized in writing to give such notices or make such demand;  and the notice or demand shall be served in person upon the owner or holder of such lien or upon his agent who is authorized to receive payment of such debt, or any part secured by the lien, or by mailing by registered or certified mail with request for return receipt, a copy of such written demand or notice to such owner or holder of the lien or to any agent of his who would be authorized to receive such payments of the debts or demands so secured by the recorded lien. This letter must be addressed to the usual known address of such owner or holder of such lien or his agent as above specified with sufficient postage prepaid;  but such notice or demand given by public mail as above provided shall be only prima facie evidence that the notice or demand so mailed was received by the addressee.