in·cred·u·lous
inˈkrejələs/
adjective
(of a person or their manner) unwilling or unable
to believe something."an incredulous gasp"
synonyms: disbelieving, skeptical, unbelieving,
distrustful, mistrustful, suspicious,
doubtful,dubious, unconvinced;
"we were incredulous when thecongressman was not moreforthcoming in his first broadcastinterview about the case"