Why did Dev feel that Sai Baba had deceived him after the Udyapan ceremony?

Dev felt deceived because he believed Sai Baba had failed to keep his promise to attend the Udyapan ceremony. Although Dev had invited Baba with great love, he did not recognize Baba when He appeared in the guise of a Sanyasi with two other companions. As detailed in Chapter 40, Dev's mind was clouded by a 'veil of Maya,' leading him to believe the guests were simply uninvited. He later wrote a letter to Jog expressing his disappointment, stating, "When I invited Baba with love, He told me, who had sought refuge, 'I am coming.' But it all turned out otherwise; I don't understand this at all."