Why did Dev fail to recognize Sai Baba when he appeared as a Sanyasi?

According to the account in Chapter 40, Dev's failure to recognize Baba was due to a 'veil of Maya' and a state of delusion. Dev himself later realized his mistake, explaining that the Sanyasi had previously visited him to collect funds for cow protection before the Udyapan invitation was even sent to Baba. This prior context fixed the Sanyasi's identity in Dev's mind as just a guest seeking a meal, not the divine master in disguise. He lamented that he forgot to pay attention to Baba's specific words: 'When I come for the meal, two others will come with me,' which would have been a clue. This prior encounter created a mental block, causing his vision to be 'so confused.'