I don't think it's you. It's just this character. Spacing is extremely important, but I've been getting most of my damage when impatient players overextend or when I backdash and my opponent tries to do a medium ranged, slow string. If you're patient and/or a zoner, you just mop up Robin. Point in case being Combo Breaker. Hayatei made it extremely far on pure match up unfamiliarity. Most of his damage (from what we could see) was from him getting a stray hit and people not knowing how to deal with 212 birdarang. That and mb sword dance.
Once people learn to punish the gap or wait for the mb and just poke, that won't happen anymore either. When he ran into Biohazard's Harley, it was free af. He couldn't get in or open her up. Hell even Compbros came dangerously close to beating him. If he hadn't gave away all that damage trying to wake up through 212 birdarang and actually reacted to birdarang full screen with canary cry, he probably would've won too.