The Caves of Androzani - S21-E6
Factual error: Sharaz Jek's monitor that displays the tunnels and his androids is inaccurate. The white blobs are, as we learn later, supposed to represent his androids. He tells the Doctor that the green area is held by the army, yet on the screen the green area is populated by androids, so they could not have had control.
The Caves of Androzani - S21-E6
Factual error: When the Doctor is trying to land the ship, from the video screen it appears that they are moving towards the planet way too fast to make such a safe and quick landing. Also, the ship doesn't seem to have even penetrated the planet's atmosphere yet it lands seconds later.
Answer: TARDISes are generally available for properly authorised use on Gallifrey; they're not usually assigned to a particular Timelord on a long-term basis. The Doctor stole his when he left his homeworld.
Tailkinker ★