Hello, i don't know what happened with your code, I started programming in SFML a day ago XD, but i think you could do this:
in the main function you declarate the dt and the clock, you should add a multiplier too.
then in the main loop:
dt = clock.restart().asSeconds();
if you want movement you should do something like this
if (sf::Keyboard::isKeyPressed(sf::Keyboard::'Key'){
vector2_variable.axis = 1 * dt * dtMultiplier;
}
shape_or_sprite.move(vector2_variable);
and that's all i didnt test it but if it fail surely be a nuisance