Hello @Minh245
Check your availability settings: Your calendar will automatically block nights to fit your listing's availability settings such as availability window, minimum nights, preparation time, advance notice, and restricted check-in. You can find the specific reason for why a date is blocked when you tap or click on blocked nights. You can open these blocked nights by overriding settings for select nights only or edit settings for all nights.
Also check if you already uploaded your valid ID, require every booking guest and every listing Host to be verified. If you haven’t verified your identity, your calendar will be blocked and you won’t be able to receive new bookings until this step is completed.