Infested Pit Dungeon Key Didn't Register After Logout.

I did the lava spider quest yesterday, and then got the key to the dungeon, ran to the entrance, and right clicked the key man with the key so that I could run the dungeon immediately today. I then logged out before entering the dungeon.
I logged on today and could not enter the dungeon.
What do I do to fix this?

 

each key only gives access to one run of the dungeon. you'll need to find another, dropped by infested pit key guardians. they can spawn at the river east of the dungeon, around detlas, and near the road to time valley, among others.

alternatively, you could buy a key from the trade market

 

When you give a key to the key collector you have a limited amount of time to enter the dungeon. Around 2 minutes once you give the key. Though you can disconnect inside the dungeon, and you will remain there until you log back on as a way to avoid it in future. The person above gives good advice on were to get more keys.