Nothing 2a charging issue

get a poco charger, 2nd option is vivo of required wattage...

Link mentions issue with cable also. 

Have you tried getting that too?

Unfortunately Oneplus 65W charger is oos now, I recommend that with a type c to c cable for nothing phones.

Saw one video sayin the same but software update fixed that issue

Bdw use that 65W gan charger from nothing ( CMF )

Ya it will cost u 2500 bucks approximately but that will give you the best charging result

Try clearing battery stats

*#9900#

Batterystats Reset

Then Turn OFF and ON fast charging option.

Restart

Try a different charging cable, certified for fast charging.