Coup de grace to the charged Higgs solution of $P_5^{\mathrm{\prime }}$ and $R_{D^{(\ast )}}$ discrepancies

We consider a general two Higgs doublet model which can simultaneously solve discrepancies in neutral B meson decay ($b\to s\mathrm{\ell }\bar{\mathrm{\ell }}$ distribution) and charged B meson decay ($b\to c\tau \bar{\nu }$) with a charged Higgs. The model contains two additional neutral scalars at the same mass scale and predicts distinctive signals at the LHC. Based on the recent same-sign top search by the ATLAS collaboration, we found the constraint on the scalar mass spectrum. To probe the remaining mass window, we propose a novel $cg\to t\tau \bar{\tau }$ process at the LHC.