ShipStation requires the API keys to be rotated periodically. You will receive a notification from ShipStation with a reminder of the expiration date for the current API keys. Details from ShipStation can be found here: ShipStation API
Create the new ShipStation V1 API key in your ShipStation account before adding it to the ShipStation settings in Pio.
Update API keys in Pio
Navigate to Pio Admin > System > Software integrations > ShipStation > Account. Add the new keys to the API key and Secret key input fields:
Select the green 'Update API keys' button to confirm: