Zoom-in view of the anomaly region of the lensing light curve. The inset in the top panel shows the enlarged view around the first peak. The solid, dotted, and dashed curves drawn over the data points are the model curves of the 3L1S, higher-order 2L1S, and standard 2L1S solutions, respectively. The three lower panels show the residuals from the individual models. The curves of the 3L1S and higher-order 2L1S models are difficult to be distinguished with the line width.