I am unable to create a return through the Blueair return portal

First, ensure it has been under 30 days since you placed the order as orders beyond this return window cannot be returned.

Make sure you are attempting to return the item to the portal for the appropriate country. See U.S. and Canadian links below:
US and CA: https://www.blueair.com/apps/returns

If you are still having issues please contact the Blueair customer support team