Studio 2019 now opening as default application

I'm running Studio 2017 and Studio 2019 on my PC and have followed the installation instructions. However, 2019 is now my default application. I had an issue where my PC restarted for updates with an open job in Studio 2017. This caused an error in the 2017 package and the job disappeared from my project list. Double clicking on the sdlproj file opened the partially complete job in Studio 2019 but there was no way of choosing to open it in Studio 2017 instead. I was only able to open the blank original project in Studio 2017 and start all over again. Anyone else experienced anything like this or know of any way to stop Studio 2019 opening as a default please?