After Barcelona, rumours started doing the rounds that Toro Rosso owner Red Bull was considering ousting the New Zealander and replacing him with Pascal Wehrlein or Antonio Giovinazzi.
“I was surprised when I heard that,” Hartley said in Monaco. “I have a contract.”
The Le Mans winner said he is used to criticism and rumours.
“There are always people to criticise you but as a driver you’re always your fiercest critic,” said Hartley.
“The last couple of races haven’t gone as we wanted, but I got my first point in Baku and in the first three races of the year I was ahead of my teammate twice in qualifying.”
Hartley continued: “There are always rumours and as a driver it’s a good idea to not read too much.
“I’m a team player and I work very hard behind the scenes. I know what I can do and I think people sometimes have a very bad memory, so the situation changes quickly.
“It could be a whole different story next week,” he added.