Read Genesis 13:7 Using Other Translations
And there was a strife between the herdmen of Abram's cattle and the herdmen of Lot's cattle: and the Canaanite and the Perizzite dwelled then in the land.
and there was strife between the herdsmen of Abram's livestock and the herdsmen of Lot's livestock. At that time the Canaanites and the Perizzites were dwelling in the land.
So disputes broke out between the herdsmen of Abram and Lot. (At that time Canaanites and Perizzites were also living in the land.)