Tawatur means that in every generation from the time of the Messenger of Allah ﷺ onward, the Quran was transmitted by such a large body of people that their agreement upon a lie or shared error is considered impossible.
• Think of a continuous chain of generations: the Companions → the next generation → later generations → the Ummah today.
• At every stage, a large body transmitted the Quran onward.
• The Quran preserved in the Mushaf reached us through this continuous mass transmission.
A report known through only a limited chain is not treated as Quranic wording merely because it discusses religion.