Spin orbit torque (SOT), arising from spin-orbit coupling-induced spin currents, provides efficient control of the magnetization direction. SOT characterization that involves analyzing the first and second harmonic Hall resistances are typically done in a low-current regime, distinct from a high-current regime, where SOT-induced magnetization switching occurs. In this study, we investigate the azimuthal angle (ϕ)-dependent harmonic Hall resistances of a Pt/yttrium iron garnet (YIG) layer across a wide range of measurement currents. Under low-current conditions, conventional ϕ-dependent Hall resistances are observed; the first harmonic Hall resistance exhibits sin2ϕ behavior and the second harmonic Hall resistance comprises cosϕ and cos3ϕ terms, associated with damping-like and field-like SOT, respectively. Interestingly, with an increase in the current, higher-order angular-dependent terms become non-negligible, referring to the sin4ϕ and sin6ϕ terms for the first harmonic and the cos5ϕ and cos7ϕ terms for the second harmonic Hall resistances. We attribute this unconventional angular dependence to the nonlinear current dependence of SOT, emphasizing its relevance to understand the magnetization dynamics during SOT-induced switching under large currents.