First of all, that needs to be substantiated. Second of all, even if that happened, so what? Everyone other president in recent history (including Hillary Clinton) conceded pretty much immediately after the race was called, because they aren't bitch baby, narcissistic, insecure snowflakes like Trump. And it's common practice that the president elect gets daily intelligence briefings. By continuing to fight a futile battle, Trump is undermining national security and emboldening his base to be more unhinged and deranged, thus also undermining national security by raising tensions domestically.