On the other hand, if it really is a blown reed, there's nothing you can do to fix the reed. There are several options. You could replace the whole harp. But if it's one with replaceable reed plates (Lee Oscar, Hohner MS series, etc.) then you can simply replace the reed plates. Or, if you're a little more technically inclined, you can replace the blown reed itself.

For that last option you need to obtain a suitable replacement reed. This isn't always possible. You can look to older harps (of the same brand & model) for replacement reeds, or you may be able to buy some from the manufacturer.

Shaggy