  A search is presented for new Higgs bosons, targeting proton-proton (pp)
collision events with a same-sign top quark pair associated with an extra jet
via the processes pp$\rightarrow tH/A \rightarrow tt\bar{c}$ and pp$\rightarrow
tH/A \rightarrow tt\bar{u}$, where H and A represent exotic scalar and
pseudoscalar bosons, respectively. The study is based on data collected at a
center-of-mass energy of 13 TeV with the CMS detector at LHC Run 2,
corresponding to an integrated luminosity of 138 $\text{fb}^{-1}$. The analysis
is made based on generalized two-Higgs-doublet model (g2HDM). It targets the
new Higgs masses ranging from 200 GeV to 1TeV and extra Yukawa couplings,
$\rho_{tu}$ and $\rho_{tc}$, from 0.1 to 1.0. Two scenarios are studied, in
which only one of H and A exists or in which they coexist and interfere. No
significant excess above standard model predictions is observed.
