Ajt comes with a spring , I haven't had issue yet ,I did not have this issue with the OEM fob, but I did with the AJT fob, and it is maddening. I think the spring was supposed to be either included or used from the other fob. I use that as a back up now rather than an everyday key, as I have the lexus key card programmed to my truck. I'm willing to bet the retainer spring inside your OEM key fob is missing, thus causing the key lock in the fob to let go and release the fob from the key......