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One of the biggest aims in exoplanet science is to understand how planets and their atmospheres evolve. Among the several challenges faced while inching towards this goal is the severe lack of observational constraints on the high-energy environments of young exoplanets and their early history of atmospheric escape. In particular comma we do not know how well Neptune-sized and smaller planets can survive atmospheric erosion during the first billion years and retain their primary atmospheres. In this context comma the recently discovered planet DS Tuc A b (45 Myr) is the best target to study atmospheric escape in the first 100 Myr in the life of a Neptune-sized exoplanet comma and is likely going to become a testbed to investigate the primordial chemistry of exoplanetary atmospheres with JWST. A previous transit observation with HST suggest that this planet is currently undergoing intense hydrodynamic escape comma but the result is ambiguous due to insufficient phase coverage and potential stellar activity contamination. In this program comma we aim to observe two more transits comma which are necessary to confirm that the feature is not spurious and to study the shape of the planet.s exosphere. Either a detection or a non-detection will be crucial to interpret the evolution of exoplanetary atmospheres of this young planet and other similar worlds.