You cannot kill those corners just by blocking the two stones on the second line. That’s why white always pushes twice in the joseki, to prevent the block from being sente. You had a winning position in this game until you took gote too many times in the end. You should have gotten the hane at C12, but instead you connected at J11 seemingly out of habit. Look how solid your group is and how many stones you have in the area. It doesn’t look like black cutting or clamping leads to anything, so unless you have a concrete reason (based on reading) to connect like that you must resist the urge to do so.