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We present a detailed study of a confined circular flare dynamics associatedwith 3 UV late phases in order to understand more precisely which topologicalelements are present and how they constrain the dynamics of the flare. Weperform a non-linear force free field extrapolation of the confined flareobserved with the HMI and AIA instruments onboard SDO. From the 3D magneticfield we compute the squashing factor and we analyse its distribution.Conjointly, we analyse the AIA EUV light curves and images in order to identifythe post-flare loops, their temporal and thermal evolution. By combining bothanalysis we are able to propose a detailed scenario that explains the dynamicsof the flare. Our topological analysis shows that in addition to a null-pointtopology with the fan separatrix, the spine lines and its surroundingQuasi-Separatix Layers halo (typical for a circular flare), a flux rope and itshyperbolic flux tube (HFT) are enclosed below the null. By comparing themagnetic field topology and the EUV post-flare loops we obtain an almostperfect match 1) between the footpoints of the separatrices and the EUV1600~\AA{} ribbons and 2) between the HFT's field line footpoints and brightspots observed inside the circular ribbons. We showed, for the first time in aconfined flare, that magnetic reconnection occured initially at the HFT, belowthe flux rope. Reconnection at the null point between the flux rope and theoverlying field is only initiated in a second phase. In addition, we showedthat the EUV late phase observed after the main flare episode are caused by thecooling loops of different length which have all reconnected at the null pointduring the impulsive phase.

Flux rope, hyperbolic flux tube, and late EUV phases in a non-eruptive circular-ribbon flare