Hi Gui Mei,
It is important to treat your pet bird against feather mites. Skin flakings are only sequelae of the mites which is a normal pathological reaction of your pet's skin. It would take some time for the healing process to regain the skin's health and vitality.
If irritation persists due to the spray solution, stop and refer to your veterinarian at once for alternative treatment. It is important, moreover, to follow the recommended dose and dosage interval of the product that you are using to avoid unwanted side effects. It is ideal too to check if the product you are using is highly effective and intended to kill the feather mites based on its active ingredients.
We suggest to do the following:
1. Stop the use of the solution for the time being (unless indicated the product you are using that irritation are normal consequences - usually clearly labeled on the product)
2. Provide your bird with balanced diet coupled with omega fatty acids that may help restore your pet's skin health and vitality.
3. Provide vitamin/ mineral/ immune booster supplements to your bird to support its recovery.
4. If signs, persist refer immediately to your veterinarian.
Eliezer M. Bauzon, DVM RN