Close caption phone...
You mean you have a TTY or CapTel or???
To call for relay service that relays/interprets for you and the persons on the other line...
CapTel should be set.
TTY, you may need to call a certain number for relay service:
some use 711 and then they'll guide you when you give them the number you want to make a call to
or check some of these websites for relay serivce:
http://relayservices.att.com/content/2/tty_relay_2.html
http://www.fcc.gov/guides/711-telecommunications-relay-service
Some states different with Relay Services:
Ohio:
http://www.puco.ohio.gov/puco/index.cfm/consumer-information/consumer-topics/ohio-relay-service/
New York: http://nyrelay.com/
Texas: http://relaytexas.com/english.html
And many more -just find your state online.
More info about TTY and TTY Relay Services:
http://www.nad.org/issues/telephone-and-relay-services/relay-services/tty
http://odr.dc.gov/release/telecommunications-relay-service-and-tty-guide
Other alternatives...
Online relays:
http://www.ip-relay.com/
Video phone Relay for sign language users can be found online as well