John Gill Commentary Joshua 17:12

"Yet the children of Manasseh could not drive out [the inhabitants of] those cities; but the Canaanites would dwell in that land." — Joshua 17:12 (ASV)

Yet the children of Manasseh could not drive out [the
inhabitants] of these cities
Mentioned in (Joshua 17:11) ; they had not strength at first to do it, or were negligent and slothful, and suffered them to dwell among them, and did not take the advantage they might have done; and afterwards it was too late, they became too strong and numerous for them, at least for a time:

but the Canaanites would dwell in the land ;
whether they would or not.