Comparison in the N-band between the VLTI/MATISSE data of 3 Puppis (in colour gradient from green to yellow), the best-fit MC3D model from Meilland et al. (2010) (in red) composed of a single centred Gaussian component plus an extended background, and the same MC3D model combined with two elliptical Gaussian components (i.e. {MC3D + 2EG} model; in blue) to account for the bright SE asymmetry and the fainter NW model provides a significantly better fit to the MATISSE interferometric observables than the original MC3D model constrained by MIDI data, with a reduced chi-squared of 24 versus 117. Top plot: Squared visibilities (V²) in logarithmic scale as a function of spatial frequency. Bottom plot: Closure phases (CPs) as a function of spatial frequency.