Trunk not opening with key

I can only open the trunk of my 98 calv z24 with keyring trunk release and not the key. Someone told me that there is a button on the inside of the trunk that only allows the keyring release to work. I look but didnt see any.

please help

I am having the same problem but the oppisite I cannot open the drivers door or the trunk with the key ring just with the key itself. All other doors open with the key ring. Weird sh...

the damn plastic works better than steel theory at work there is a plastic mechanism that connects and actuates the cable from the drivers seat to the lock cylinder ... the only problem is that plastic is softer than steel so the clip and other connecting parts are eaten away by the steel and the lock now rotates ... the whole cylinder ... open the trunk and watch ... ferreal they built it that way. should be able to get one from chev dealer or napa auto parts etc.