Left: co-addition of the Na doublet lines as a function of orbital phase in the planet rest frame considering the two transits. The vertical black dashed dotted lines represents the expected position of planetary sodium. The two horizontal black dashed lines are the t₁ and t₄ contact points while the loosely dashed lines are the t₂ and t₃ contact points. The two orange lines encompass the FWHM of the stellar local lines causing the RM effect. The sodium stellar line core with low S/N is clearly visible in all phases. Right: co-addition of the Na I doublet averaged across the two transitsin gray and binned by ten elements in black. The vertical blue dash dotted line represents the expected position of planetary sodium. The red curve is the best Gaussian fit on the data.