You need a Fillet, you might not be able to add one of you already have a chamfer. Options will be Radius of Fillet
Thanks OM. Couldn't find the "fillet" command, but your response prompted a thought.
I selected "Line" and one of the options for a line is "arc" next to Line Lock (whatever that means). Selecting arc, I was then able to draw an arc from one intersection of the chamfer to the other. Then I deleted the chamfer segment. Seems to work.