LOTR: If Trolls Turn To Stone In Daylight, Why Don't The Trolls Who Fight In The Battle Of Minas Tirith?

During the final chapter of Book 1 of the Fellowship of the Ring, entitled ‘Flight to the Ford,’ the company of four hobbits led by Aragorn the ranger are making their way to Rivendell, having just faced the Ringwraiths in a perilous encounter at Weathertop. They are journeying through lands known as troll country, and Merry and Pippin are terrified as they find 3 trolls whilst scouting the path ahead of the others.

Source: Gamerant