Callouts and labels where the text end jumps off the visible screen - how to prevent this?

I am an inexperienced Composer user. When I create callouts or labels, sometimes the text end of a callout of label seems to suddenly "jump" off the visible area of the screen and I cannot retrieve it. My colleagues experience similar frustrations when creating and working with calloouts and we are unable to figure out why this seems to happen. To get around this, I have to delete the affected callout and create it again. I started using magnetic lines to help prevent this, and this helps, but does not prevent the problem entirely. I am not sure that I can explain the problem in a better way. Thanks for any help.

Regards,

Marc Honore

SolidworksComposer