Answer:
If your instrument is not functioning properly after dropping it, the first step would be to take it to a qualified instrument repair person or a luthier. They can examine the instrument and assess the damage to determine what repairs are necessary.
In the meantime, avoid playing the affected notes or playing the instrument altogether, as continued use may worsen the damage or cause additional problems. It's also important to avoid attempting any repairs yourself, as this could potentially cause further damage and make the repair more expensive in the long run.
If you're not sure where to find a qualified repair person or luthier in your area, you can try contacting your local music store or asking for recommendations from other musicians. It's always best to entrust your instrument to someone with the knowledge and experience to properly repair it.