Can anyone advise how I can uninstall a looked addon after upgrading. I was expecting an updated version of Classifieds, even paid the update fee and no update has been forthcoming nor has there been any communications from the developer. Not only have I lost my money but also am stuck with a locked addon that I can't get rid of

You can only uninstall it or upgrade it. There are only those 2 options

Please let us know if you need assistance in removing this

Yes please, the developer is not responsive

I have created a ticket on this for you. Someone will be in contact as soon as possible