Mangesh kalaskar , via OnePlus Nord , Mar 3, 2021 : After stable update of oxygen OS 11 My phone's charging speed reduced. Very slow charged
Shailender Sharma , Mar 3, 2021 : If possible, try to charge your device with another Warp charger and type c cable to verify that there is no issue with your charger/cable.
Dresa91 , Mar 3, 2021 : This won’t help... take a look at the Screenshot.... there is already the symbol for warp charge,... hey, try this:
Caomhin , via OnePlus 6T , Mar 3, 2021 : Clean the ports on the phone, charger and both ends of the USB cable with a fine dry toothbrush or non conductive wooden or plastic toothpick carefully. See if that helps.
McJader , Mar 4, 2021 : Yes, many people have observed a dip in charging speeds after receiving the stable OOS11 update. Best is to give it some time to settle down, and report it as a bug here : https://forums.oneplus.com/feedback/