Sims 3 key/license limit problem?

i tried to install sims 3. at the beginning it asked me for key, i put it in. then i opened the launcher and it asked em for a key again. i put in the same exact key and it didn't accept it. after trying a few mroe times it locked me out by same the license limit has been reached. i tried unistalling it and reinstalling it. no luck. i tried just just using TS3.exe and it gave me the same message. i looked up the de-authorization thing but did not quite understand how that would help me. is there any way to make the computer forget i tried to enter the key or something because now it's not even asking for a key