David Miller and Heinrich Klaasen stitched an unbeaten 139-run stand as South Africa go 1-up.
With this victory, Australia has taken a 1-0 lead over WI in the two-match series.
South Africa beat India by 49 runs in third and final T20I at Indore on Tuesday. India won series by 2-1.
The BCCI will be naming a replacement for Bumrah in the squad for the marquee tournament soon.
Miller scores 106* (47-ball) in vain as the hosts register their first T20I series win against South Africa at home.
Dawid Malan, Chris Woakes star with bat and ball as England power to series win.
Maiden ODI call-ups for Rajat Patidar and Mukesh Kumar for the upcoming three-match ODI series against South Africa, starting October 6.
England have announced a bumper home schedule for the summer of 2023, which will include a five-match Ashes and a one-off Test match against Ireland.
Phil Salt smashes an unbeaten 88 from 41 balls as England storm to an eight-wicket win over Pakistan in the sixth T20I.
Pakistan take a 3-2 lead in their Twenty20 series against England with a six-run victory in a low-scoring match in Lahore.