One front brake is doing more work than the other. Nine times in ten that is a sticking calliper or a seized slider on the lazy side, which also means that wheel runs hot and the pad on it is the thinner of the two.
We get the wheels off, measure both sides and show you the two numbers. A rebuild kit fixes a calliper that is only sticky; a pitted bore needs the unit. Pulling under braking is not an alignment problem, and anyone who sells you an alignment for it has not looked.