I bought woocommerce product filters some time ago. I got a notice that there was an update. I downloaded the update and not it is saying that I have an invalid license. I have tried several times to put the license number in and it always gives me the same error.
Before update have you removed the installed and activated plugin? and install a new fresh of the update download! If yes then may be license related any data loss. Please contact plugin author (How to Contact your purchased Item Author) and let them know. Author will help you.