you will have to go to a shop that has the tool to reprogram the security system with all the keys that are being used so they can be reprogramed to the security system.
Everything you need to bypass this system yourself can be found on this link.
I had that same problem and it took me forever to figure out what was wrong. You are probably using an aftermarket key as was I. The stupid little plastic/metal chip in the shaft of the key is for the security system. Sometimes if you insert the key and turn too fast it sets off the security system. To solve the problem go get another key made from a different key maker, they cost around $15-20. Or, insert the key slowly and turn the ignition slowly. Or go get a good key from the dealer, I've heard it may be ~$50 for this key but it should work the best. FYI I still just use my aftermarket key and just deal with the occasional no start wait 3 min ordeal. Good luck.