so what, unless Biden directly calls Putin with a full break down of the attack, it wasn't enough?
and for you to keep saying we didn't give Putin enough information through the proper channels, you know more about it than the Russians did.
you know when the attack was supposed to happen, you know where the attack was supposed to happen, who is supposedly behind it, you know exactly all the various communications that happened and in what forms and forums it took place. you apparently know all of that because America made the warning in a public enough way for the information to be readily available.
that all sounds like enough information to stop an attack. or at least be prepared for it. If that level of information isn't good enough I am not sure why/how more information or the same through another method would have been satisfactory.