Hi Ian,
Thanks for posting your question to the forum and welcome. When we see posts like this we find that there is another account that was signed in under and that is where the files are. Also in the upper right hand corner is the name of the hub. For example, A360 Drive says A360 Drive. There will be a dropdown arrow that lets you switch to A360 Team or Free depending on what you have. You may want to check that as well.
Give that a try and please let us know how it goes. And again welcome to the forums.