Parallels Pro - License validity after 1Year... Forcing to upgrade/buy and doesn't start...

Hi, I had previously purchased Parallels Pro... but it stopped working after exactly 1Year and was forcing to upgrade and it won't boot the OS up... Has this restriction changed... as the purchased Software must be supported until you sunset it... and your documentation never shows anything on this subject... Please clarify this for me to decide on which version to purchase...