Problems with using my key card at a hotel

I was in Washington, D.C. attending the Alzheimer's Assoc. Advocacy Forum. The hotel that I'm staying at is quite large and has more than one set of elevators in different areas of the lobby and signs that say East or West. I know that when I took the elevator up to my room, it was very confusing for me. It was in the evening when I went back to my hotel room. Unfortunately, I couldn't get my key card to work. I thought that I might have gone to the wrong room. I took the elevator back down to the lobby and I told them what happened. They confirmed with me which elevator that I needed to take to get to my room. I was told to go back to my room and security would be up to reset my key. After finding my room again, while I was waiting for security, I decided to try the key card again. I tried my key card this time it worked! Boy was I happy! I used the phone in the room and called the front desk to let them know.