Roll back to previous Photoshop version

I have a $5,000 Canon printer that won't print because of Adobe.  The Canon print program won't work with Photoshop 22.0.0 and Canon told me to roll back to a previous version of Photoshop.  I attempted to unintall version 22 and reinstall an older version but there's no option to do that.  I've tried contacting Adobe customer support at least a half-dozen times.  I gave up on "chat" option after 45 minutes with no response.  A number of phone calls have all ended with silence on the other end of the phone line.  Adobe has set a new standard for awful customer service!