I have a regular rotary attachment, but will be upgrading to the pro.  I’m very new to this.  I’ve been watching tutorials, but am still having issues.  I’m attempting to wrap around the entire tumbler, but am having issues with the dimensions.  I’m able to adjust one, but when I go to adjust the other it changes the one I’ve already fixed to my needed dimensions.  Why won’t it let me set both dimensions?  What am I doing wrong and what can I do to remedy this?

Thank you!!!!