Quantum properties associated with topology [1, 2] are distinguishable in their immunity to a range of variations. The extent of this range, which is found to vary ubiquitously in real systems, marks a robustness fundamental to all topological orders. The underlying mechanisms that potentially obscure topological protection are usually associated with effects of disorders either inherent to the systems or imperfections introduced during sample fabrications [3]. Suppression of the influence of disorders is an essential challenge facing realistic precision quantum applications. So far, relevant works concentrate mostly on the dissipationless edge states (i.e. in the integer quantum Hall effect (IQHE) [4, 5]) in the context of the ability of sustaining the absence of backscattering [6]. The findings of the edge effects [7] alone, however, are insufficient to address the more general phenomena of topological breakdown which necessarily involves the bulk effects. In this study, simultaneous measurements of the bulk and edge responses are carried out independently in an IQHE, hosted in a Corbino two-dimensional system, brought to the verge of a topological breakdown. Accurately measured insulating and conducting responses reveal exceptional topological robustness in a strongly correlated limit where the cause of the breakdown is identified as back-scatterings arising between dissipationless current paths of opposite chirality facilitated by rare local resonant tunnelings. A unique "staircase" bulk feature, captured in real-time correspondence with the emergence of edge dissipation and deviation from Hall quantization, indicates a dielectric reconstruction effect influenced by enhanced impurity screening due to strong electron-electron interaction. These findings provide insight on suppressing disorder effects as an important means of reaching topological robustness.