I suggest you retake the test. I was facing similar problems last year and i didn't retake the test. I am really regretting it. Interview invites don't mean anything. Currently, I've got interview invites from wharton, kellogg tuck and more, but was recently rejected from Kellogg. I believe it's the GMAT score that dragged down the overall application. RETAKE! I wish i did that.... and make sure you score 750.