TESS photometry of TOI-1438. Top: the de-trended TESS time series colour-coded according to sector; from black in Sector 14 to light copper in Sector 81. The data from Sector 74 is under the red cross and was excluded from the analysis. In total, there are 150 and 79 transits of planets b and c, respectively (excluding Sector 74). Middle: the phasefolded light curves for planets b (left) and c (right). The unbinned data are shown as small, grey markers, and the larger markers are ~10 min binned data colour-coded as in the top panel. The best-fitting models are shown as the white lines. Bottom: residuals from subtracting the best-fitting models from the data.