Same here. It happens, when you are touching a block, having the "Up" arrow pressed and then pressing the "Jump" key: Nothing happens. However, if you release the "Up" arrow and then press "Jump", THEN you will jump. And if you again press "Up" while you are jumping you can get on top of that block.
Same here. It happens, when you are touching a block, having the "Up" arrow pressed and then pressing the "Jump" key: Nothing happens. However, if you release the "Up" arrow and then press "Jump", THEN you will jump. And if you again press "Up" while you are jumping you can get on top of that block.