The command "/enchant" can't enchant the right level

If you get a repeating command block and block it on the ground, and input the command that "/enchant @p 9 1" in it, and block a redstone block next to it, then it will activate.

Now we take a golden sword from the inventory. We can see the enchant on this sword is "Sharpness II", not "Sharpness I"!

So this is the bug.

If I get a normal command block and input the command in it, then activate it, it will enchant "Sharpness I".

But if I activate again, it will enchant "Sharpness II".

Do you think when I activate it again and again, it will overlay endlessly? No. When I activate it for three times, it will stay at "Sharpness II", not "Sharpness III".

This is a bug. I wanna make a map of bedwars, but this bug lead to all the enchants in level 1 will Will not take effect.