You write that you tried to speak to the person about covering her hair with a kerchief [but you were not successful] and you did not want to apply force or make a commotion.

[You were correct in doing so,] for Heaven forfend, Heaven forfend [to act in too forceful a manner], for the path to success is not through anger but through gentleness. Merely explain that Kisui HaRosh brings with it success from G-d's hand for herself, her husband and her children Sheyichyu.

This being so, what possible comparison can there be between the difficulty (even if this were to be considered a difficulty) in wearing a kerchief in relation to what G-d rewards for doing so.

Excerpt from Igros Kodesh, Vol. VI, pp. 117-118