Is a woman's prostration considered incorrect if her shawl prevents her forehead from touching the ground during prostration, and must she repeat the prayer if she moves her shawl while prostrating to enable her forehead to touch the ground?

There is no objection to a woman prostrating on the edge of her head covering (shal), because it is not obligatory for the forehead to directly touch the ground. Prayer is valid when prostrating on a turban's fold, a sleeve, or a garment's hem. There is also no harm in a woman removing her head covering from her face to prostrate on the ground if needed, as this is not among the numerous actions that invalidate prayer.