Why did Dev believe that Sai Baba had deceived him regarding the Udyapan ceremony, and what was Baba's response to this accusation?

Dev felt deceived because after he invited Sai Baba to his Udyapan ceremony, he believed Baba did not attend. This led him to feel disappointed and write a letter to Jog complaining that Baba's promise had failed. As Chapter 40 explains, when Jog presented this to Baba, Sai responded by revealing the truth. Baba was surprised at the accusation, saying, "He says I deceived him with My words of assurance; tell him, 'You did not recognize Me! Why then did you call Me?'" Baba clarified that He did attend the meal in the guise of a Sanyasi with two other companions, thus perfectly fulfilling His promise, even though Dev's delusion prevented him from recognizing the fact.