a mystery in keeping it postive

I got a letter from the bank about the new procedure for the safe deposit box. ??? I don’t have one.
Turns out my parents had one and my name was on the “can access” list. OKAY.
I don’t have a clue if/where I have a key and they cannot open the box without a key. A friend drove me to the bank. I brought my mother’s keys. Not one would fit. I searched the apartment and found MANY items, and a few keys. If I go back, I’ll see if any of the newly found keys would be appropriate. Otherwise, the mystery continues.