your github oauth token for github.com contains invalid characters composer update

Go to C:\ Users\ UserName\ AppData\ Roaming\ Composer Open the auth.json file. Clear everything and paste the below code

{
	"bitbucket-oauth": {},
	"github-oauth": {},
	"gitlab-oauth": {},
	"gitlab-token": {},
	"http-basic": {},
	"bearer": {}
}