As has been posted before, Lincoln sent the US Navy to re-supply, though the Sumter garrison was getting foodstuffs from on shore.
Abe was flicking boogers at what he thought were push-overs.
300,000 plus dead guys under his direct command showed what a n00b fool he was...
So when Beauregard ordered the supplies cut on April 7, he was ignored and the supplies kept flowing? When Major Anderson wrote his superiors that their supplies were running out he was lying?