At one point he was losing 0.5-1sec per lap to Max, while Max's tyres were EOL. Lewis did seem to improve and catch-up for a few laps, but then fell back again, which is also possibly down to traffic.He didn't need to overtake on track, he needed to be within a pitstop of Max to take a position. As he exited his pitstop that was very achievable but he fell back a long way instead.
He should've had more pace though. Charles was in dirty air for a lot longer but managed better times.