Rishidatta is not a standard, well-attested name in the core Jain scriptures for which a specific “previous birth” story is given. In Jainism, every soul has countless past lives, and the Tirthankaras’ lives before enlightenment are described in various texts, but there isn’t a canonical, widely accepted record of a figure named “Rishidatta” and his previous birth.

If you can share more details or confirm the spelling (for example, whether you meant Rishabhanatha/Adinath or another jina in a particular text or tradition), I can give a precise, tradition-faithful explanation about that figure’s past life according to Digambara or Śvetāmbara sources.