Rancher Helm installation “--set bootstrapPassword=“rancher”" isn’t working. When we login for the first time, even if we give the bootstrap password set in helm command, it says unauthorized. Did anyone faced this issue?

You could see what Helm is actually setting the password to with

kubectl get secret --namespace cattle-system bootstrap-secret -o go-template='{{ .data.bootstrapPassword|base64decode}}{{ "\n" }}'

It might not like the quotes, or be including them literally, but not sure. That command will atleast show you the verbatim password