I heard Tarkhad made a mistake with his offering. What happened and how did he feel about it?

Yes, Chapter 9 recounts this incident. Babasaheb Tarkhad, who had promised his son he would offer Naivedya daily, forgot to do so one day because he was preoccupied with his business at a large mill. As a result, the entire household ate their meals without the offering being made first. When Tarkhad sat for his own meal and realized the sugar candy Prasad was missing, he was overcome with remorse. He considered it a 'great sin,' not just a mistake, and prostrated before Sai's image with tearful eyes, begging for forgiveness and feeling utterly helpless.