Hello, I have loaded up HotS for the first time in a good few moths to have a bit of fun and it would appear I am missing some characters that I already owned before hand. It now claims I have not earned the characters and appears I need to repurchase them.
sure you didn’t log into the wrong region?
That or that the characters were simply free to play that week you stopped playing?
I would probably test Insomnias theory first by changing the region in your launcher before clicking “Play”.
Thanks guys. Think I was having a senior moment! 
It happends, glad it worked out!