When the hammer is raised only to the half cock position, the cylinder bolt lock is not engaged with the cylinder. This allows the cylinder to be turned for loading and usually, the chambers in the cylinder are not lined up with the barrel.
The only time the cylinder lock bolt fully engages the notch in the cylinder to align the chamber with the barrel is when the hammer is raised higher than the half cock position. By the time the hammer reaches the full cock position, the cylinder lock bolt should be fully engaged with the cylinder notch and the cylinder will not rotate.
This engagement of the locking bolt with the cylinder is maintained as the hammer falls from its full cock position to the fired position keeping the chamber and the barrel aligned.
In other words, your gun is working just like it is supposed to work.