Upper panel. Observation from May 25, 2023. Lower panel. Observation from April 9, 2024. Top. Best fit synthetic spectra (red) for the H-band observations (black) including the non-magnetic synthetic spectra (dashed-blue). Bottom. Posterior distributions of the inference parameters (left) and average surface magnetic field strength (right) for the same observation. Vertical lines are showing the median and 68% credence regions in the same way as in Fig. 2.