I can't download the app

I just purchased a POS but I'm having a hard time using the software. 

I was able to create an account but something happened, so I had to uninstall the app, but I can no longer install it back. I've been trying to install the free version but I'm getting multiple errors. It all started when I tried to back up the file. 

 

 

I hope someone can call me or do remote access to help me fix this. 

 

Thank you,

John Patrick