Samung Galaxy Tab: I inadvertently deleted my Wifi connection and cannot re-connect.

Half asleep last night my finger inadvertently landed on the "forget" button which has wiped out my Wifi connection. I rang Telenet this morning and got on to an irritable guy with a snotty attitude whose main interest was in establishing who was to blame, although I had clearly stated it was I who had clicked on the "forget" button. I have the login code and the password but simply cannot get the system up and running again. Each time it simply asks me to enter the password again. Telenet man was useless: "I don't know every type of tablet...." that kind of response. Anyone out there who can help?