Both my sisters -in-law have been frequenting 'Molvis' who put them into a trance like state.

Answer

The two fake, impostor 'molvis' need to be whacked and perhaps crucified for their vulgarity and, lies and slander. Their action is haraam. The two frauds are guilty of a grievous sin and slander against you. It is quite possible that shaitaan had tricked them and your two sisters-in-law. Shaitaan is able to imitate and impersonate people – their appearances and voices. But the 'molvis' are guilty of the great crime of having created fitnah and this enduring family rift and dissension.

You know that you are innocent and have not dabbled in the filthy acts of sihr (evil magic/witchcraft). Dabbling in such Satanism eliminates Imaan. As long as you are aware that you are innocent of the slander which they are levelling against you, don't go to see any 'molvi'. Such 'molvis' will make you an addict of non-existent black magic. These 'molvis' with their tricks create considerable problems for people. They ruin family relationships and people become victims of satanic imagination under their spells and trances. Supplicate to Allah Ta'ala for protection and safety. He will protect you and clear your name.

Adopt sabr and do not become engaged in any mud-slinging match with them. Leave them to their haraam antics. When the mazloom (oppressed one) turns to Allah Ta'ala for aid, then He takes up the mazloom's defence. So while their slander is causing grief to you, tolerate it with silence and trust in Allah Ta'ala.