129. Notice shall be sent to the parties within reasonable time before the hearing or within the time fixed by law, stating(1) the purpose, date, time and place of the hearing;
(2) that the parties have the right to be assisted or represented, and listing the classes of persons authorized by law to assist or represent a party before the Tribunal;
(3) that the Tribunal has the authority to proceed, without further delay or notice, despite the failure of a party to appear at the time and place fixed if no valid excuse is provided.