Turn Signal Wiring

So I am installing blinkers on an 86 700 since there were none on it when i bought it. I replaced the relay and wired up the back left and back right blinkers and when I went to test my wiring they work. However, I cannot get them to stop, Either my left turn signal is on, or the right. When i push the turn signal switch to the middle the previous turn signal keeps blinking. So is the switch broken? and can it be fixed without replacing it? Thanks