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The changing-look (CL) behavior in active galactic nuclei (AGNs) is characterized by dramatic changes in the overall brightness of sources, leading to restructuring of circum-nuclear environments such as the inner accretion geometry, broad line region (BLR), and outflows. They offer a rare opportunity to witness accretion state transitions in real time, akin to those seen in stellar-mass X-ray binaries (XRBs). In this talk, I will present a decade-long multiwavelength study of the Seyfert galaxy, which captures a complete spectral state transition--from a faint, hard X-ray phase to a bright, UV- and soft X-ray-dominated state within just $\sim$10 years. Using diagnostics like the X-ray loudness parameter ($\alpha_{\rm OX}$) and the hardness--intensity diagram (HID), we identify a critical Eddington ratio ($\lambda_{\rm Edd} \sim 0.02$) marking the onset of inner accretion flow restructuring. These findings provide strong evidence that CLAGNs trace accretion physics analogous to XRBs, scaled up in mass but compressed in time.