A piano.
Open the keys with the door.
A piano.
Piano
a piano
donkey and monkey
Mon-keys Don-keys Piano keys
A piano.
A piano.
a piano
The thing that has 88 keys but cannot open a single door is a piano. The 88 keys refer to the total number of keys on a standard piano, which includes both the white and black keys. These keys produce musical notes rather than serving any function related to unlocking doors.
If you do not have keys for the doors in the game, you will not be able to open them. Even if you do have the keys, you have to use the key to open the door through your inventory menu. Once you close the doors, they are locked until you use the key to open it back up.
Are the keys in the ignition? If so all you have to do is take them out when you open the door.