What level are you on in classic mode (57, 58)?. The total points needed (IIRC) are 862000 total under classic mode. Even after you reach level 30 in legendary, you will continue to accrue XP until that threshold is met. Try playing on classic mode until you get enough points to level from from 58 to 59. I am on level 30, but hit that after I hit 59 on classic. Hope this helps.
Not sure on classic, I was 57 by the classic scale after my first play through. I’ve gained a couple levels since. I’ll keep going just don’t want to waste time if it’s truly glitched. I should have stuck to what I know and just played on the classic scale period.
