How to fix error while using LookupIn in couchbase document error: "could not execute one or more multi lookups or mutations"

I am executing the below code in my code flow and getting an error "could not execute one or more multi lookups or mutations". Please suggest if I am doing something wrong here.

I am using go SDK.

frag, err := bucket.LookupIn(id).Get("key").Execute()
if err != nil {
   log.Error("error:", err)
}