According to the fare finder the fare from Abbey Wood to North Greenwich is £1.70 off peak.
I tapped in at Abbey Wood at about 7.15pm on Thursday (off peak) took the Elizabeth Line to Canary Wharf, Tapped out and walked through the shopping centre to the Jubilee Line and tapped in again. One stop to North Greenwich and tapped out and was charged £1.80
Have I been overcharged or is the fare finder incorrect?
Neither. The default fare is a zone 3-4 fare which would be charged if you changed at Custom House and Canning Town. When you exited at Canary Wharf you were in zone 2 so you were charged a zone 2-4 fare. The system can’t give you back what it’s already taken, but when the journeys are put through the back office it will queue a 10p refund. Unless you become eligible for another £1.40 you won’t get it until 2 weeks have passed, but you will get it back.