I had the same problem when I went to a Google Voice Number. There is a whole section in Google Voice Help set aside for the issue. You will need to go to the link below and fill out the information.
Call can't be completed as dialed : Calls - Google Voice Help
I want to say it took about three months to get mine straightened out, but I am also in a very rural area and the number of peeps with Android phones, let alone using GV on them is probably slim. Most people on the help forums are seeing one month turn around times. YMMV due to the number of folks in your area with the issue.