Contradiction with Joshua 13:1
Joshua 18:1 describes the congregation assembling at Shiloh to set up the tabernacle, suggesting a settled phase, whereas Joshua 13:1 speaks of much land remaining to be possessed, indicating an ongoing conquest.
Joshua 13:1: Now Joshua was old [and] stricken in years; and the LORD said unto him, Thou art old [and] stricken in years, and there remaineth yet very much land to be possessed. [to...: Heb. to possess it]
Contradiction with Numbers 10:33
Joshua 18:1 mentions the tabernacle set up at Shiloh, while in Numbers 10:33 the Israelites were still journeying with the Ark and no permanent resting place for the tabernacle is indicated.
Numbers 10:33: And they departed from the mount of the LORD three days' journey: and the ark of the covenant of the LORD went before them in the three days' journey, to search out a resting place for them.